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A series of hybrids comprising two metal (Mn, Fe, and In) tetraphenylporphyrins axially substituted with anionic bidentate trans -thioindigo ligands (TI) were obtained. Substitution of the axial chloride anion by an oxygen atom of the dye forms short M-O bonds. Crystalline binuclear assemblies (TI •- )·{[Mn II TPP] 0 ·[Mn III TPP] + }· x C 6 H 4 Cl 2 ( x = 2 for 1 or 1 for 2 ) and (TI 2- ){[M III TPP] + } 2 · x C 6 H 4 Cl 2 (M = Fe and x = 2 for 3 , M = In and x = 1 for 4 ) were synthesized. The thioindigo (TI 2- ) dianion and metal (Fe III and In III ) atoms in TPPs maintain their initial charge states during the formation of 3 and 4 , allowing the separation of paramagnetic Fe III or diamagnetic In III ions by a diamagnetic TI 2- bridge. Strong antiferromagnetic coupling is observed between Fe III ( S = 5/2) centers in complex 3 . Partial reduction of Mn III to Mn II occurs upon the formation of 1 and 2 , leading to assemblies containing three paramagnetic centers: Mn II ( S = 5/2), Mn III ( S = 2), and TI •- radical anion ( S = 1/2). Orthogonal arrangement of TPP and TI molecules in 1 provides strong ferromagnetic coupling. Weak antiferromagnetic coupling is realized in 2 due to the rotation of the TI bridge.

The oxidation of tetraselenatetracene (TSeT) by tetracyanoquinodimethane in the presence of dysprosium(III) tris(hexafluoroacetylacetonate), Dy III (hfac) 3 , produces black crystals of {TSeT 1.5 } ●+ [Dy III (hfac) 4 ] - ( 1 ) salt, which combines conducting and magnetic sublattices. It contains one-dimensional stacks composed of partially oxidized TSeT molecules (formal averaged charge is +2/3). Dimers and monomers can be outlined within these stacks with charge and spin density redistribution. The spin triplet state of the dimers is populated above 128 K with an estimated singlet-triplet energy gap of 542 K, whereas spins localized on the monomers show paramagnetic behavior. A semiconducting behavior is observed for 1 with the activation energy of 91 meV (measured by the four-probe technique for an oriented single crystal). The Dy III ions coordinate four hfac - anions in [Dy III (hfac) 4 ] - , providing D 2d symmetry. Slow magnetic relaxation is observed for Dy III under an applied static magnetic field of 1000 Oe, and 1 is a single-ion magnet (SIM) with spin reversal barrier U eff = 40.2 K and magnetic hysteresis at 2 K. Contributions from Dy III and TSeT ●+ paramagnetic species are seen in EPR. The Dy III ion rarely manifests EPR signals, but such signal is observed in 1 . It appears due to narrowing below 30 K and has g 4 = 6.1871 and g 5 = 2.1778 at 5.4 K.

The interaction between photochromic 8-methoxy-1',3',3'-trimethyl-6-nitro-spiro[chromene-2,2'-indole] (MNSP) and cobalt(II) hexafluoroacetylacetonate yields a deep red-violet solution due to the coordination-induced transition of MNSP from a colorless closed state to a colored open merocyanine (MC) form. The resulting complex {Co II (hfac) 2 ·MNSP} (1) is obtained as crystals, and its structure at 250 K shows the coordination of two oxygen atoms from MNSP with Co II , forming a distorted octahedral surrounding around Co II . The unit cell of 1 contracts below 170 K by 5.5%, which is accompanied by shortening O-Co bonds and altering O-Co-O angles in the structure solved at 150 K. The χ M T value of 3.06 emu K mol -1 at 300 K indicates the formation of high-spin Co II ( S = 3/2) with a large orbital contribution characteristic of the octahedral surrounding. The contraction of the unit cell of 1 below 170 K provides a reversible 2.2% change of χ M T in the 170-160 K range during heating and cooling regimes without hysteresis. The electron paramagnetic resonance signal of 1 was simulated with g -values of g x = 2.342, g y = 2.364, and g z = 2.084, and an isotropic g -factor of 2.267. The temperature-dependent χ M T and field-dependent magnetization of 1 allow us to determine a positive zero-field splitting parameter of +20.1 cm -1 . A study of the dynamic properties of 1 shows slow magnetic relaxation for Co II in a static field of 1000 Oe. Magnetic hysteresis loops were observed for 1 at 0.5 and 2 K; these loops are closed in the zero field region but opened at fields higher than ±100 and 700 Oe, respectively. The collapse of the loop is observed at 5 K. Excitation of the solution of 1 with green light decreases partially the intensity of the bands of the complex, whereas subsequent exposure of this solution to UV light partially restores these intensities.

The reaction between an excess of Fe(CO) 5 with {Cryptand(K + )}(C 60 •- ) produced the salt {Cryptand(K + )} 2 {[Fe(CO) 2 ] 2 -μ 2 -η 2 :η 2 -η 2 :η 2 -(C 60 ) 2 } 2- ·4C 6 H 4 Cl 2 ( 1 ) containing negatively charged iron-bridged fullerene dimers. In these dimers, the C 60 cages are linked via two Fe(CO) 2 fragments, forming short Fe-C(C 60 ) bonds with a length of 2.070(3) Å and via two intercage C-C bonds with a length of 1.566(3) Å. Interfullerene center-to-center distance is short, being 9.02 Å. Thus, the coordination-induced dimerization of fullerenes is observed in 1 . The dimer is negatively charged, with additional negative electron density mainly localized on iron atoms and, to a lesser extent, on the C 60 cages, as revealed by optical and electron paramagnetic resonance spectra. These dimers have a diamagnetic singlet ground state with a small singlet-triplet gap of 25 K; consequently, they transfer to a paramagnetic state with two S = 1/2 spins per dimer above 50 K. Previously, different dimers with isomeric structures were obtained starting from {Cryptand(K + )}(C 60 •- ) and Fe 3 (CO) 12 . However, these dimers exhibit diamagnetic properties, owing to the formation of a Fe-Fe bond. In contrast, in dimer 1 , the Fe atoms are positioned too far apart to form such a bond, preserving the spin on Fe. We assume that both dimers are formed through the same [Fe(CO) 3 ](C 60 •- ) intermediate, but the subsequent interaction of this intermediate with Fe 3 (CO) 12 or its dimerization yields different dimers. Therefore, the starting carbonyls can control the structures and properties of the resulting dimers.

Heterobimetallic {[Co(CO) 4 ] - [In III (Pc 2- )]} (1) and (Cp* 2 Cr + ){[Mn(CO) 5 ] - [In III (Pc˙ 3- )]}·2C 6 H 4 Cl 2 (2) complexes based on indium(III) phthalocyanine (Pc) were obtained as crystals. The complexes were synthesized by single (1) and double (2) reduction of indium(III) phthalocyanine chloride in the presence of transition metal carbonyls. Complex 1 contains dianionic Pc 2- macrocycles. Thus, the coordinated Co(CO) 4 carbonyl accepts an electron in the one-electron reduction forming a diamagnetic [Co(CO) 4 ] - anion. Complex 2 contains a heterobimetallic {[Mn(CO) 5 ] - [In III (Pc˙ 3- )]} - anion and paramagnetic Cp* 2 Cr + counter cations. Therefore, in the double reduction, electrons are transferred to Mn(CO) 5 forming a diamagnetic [Mn(CO) 5 ] - anion and to the Pc 2- macrocycle forming a paramagnetic radical Pc˙ 3- trianion. Such assignments for 1 and 2 are in line with optical spectra, crystal structures and the data of magnetic measurements. The spectrum of 1 in the UV-visible range is similar to that of the starting In III ClPc. The formation of 2 is accompanied by an essential blue-shift of the Q-band of Pc as well as by the appearance of an intense NIR band at 1005 nm characteristic of Pc˙ 3- . Compound 1 is EPR silent and diamagnetic, whereas the value of the effective magnetic moment of 2 is 4.24 μ B at 300 K, which corresponds to the contribution of S = 1/2 (Pc˙ 3- ) and S = 3/2 (Cp* 2 Cr + ) spins. Both weakly coupled paramagnetic centers ( J = -0.41 cm -1 ) are observed in the EPR spectra.

A series of trianion assemblies of hexaazatriphenylenehexacarbonitrile {HAT(CN) 6 } and hexaazatrinaphthylenehexacarbonitrile {HATNA(CN) 6 } with three Fe(II) or Co(II) ions: {cryptand(K + )} 3 ·{HATNA(CN) 6 ·(Fe II I 2 ) 3 } 3- ·2C 6 H 4 Cl 2 (1), {cryptand(K + )} 3 ·{HATNA(CN) 6 ·(Co II I 2 ) 3 } 3- ·2C 6 H 4 Cl 2 (2), and (CV + ) 3 ·{HAT(CN) 6 ·(Co II Cl 2 ) 3 } 3- ·0.5(CVCl)·2.5C 6 H 4 Cl 2 (3) are synthesized (CVCl = crystal violet). Salt 1 has a χ M T value of 9.80 emu K mol -1 at 300 K, indicating a contribution of three high-spin Fe II ( S = 2) and one S = 1/2 of HATNA(CN) 6 ˙ 3- . The χ M T value increases with cooling up to 12.92 emu K mol -1 at 28 K, providing a positive Weiss temperature of +20 K. Such behavior is described using a strong antiferromagnetic coupling between S = 2 and S = 1/2 with J 1 = -82.1 cm -1 and a weaker Fe II -Fe II antiferromagnetic coupling with J 2 = -7.0 cm -1 . As a result, the spins of three Fe(II) ions ( S = 2) align parallel to each other forming a high-spin S = 11/2 system. Density functional theory (DFT) calculations support a high-spin state of Co II ( S = 3/2) for 2 and 3. However, the χ M T value of 2 and 3 is 2.25 emu K mol -1 at 300 K, which is smaller than 6 emu K mol -1 calculated for the system with three independent S = 3/2 and one S = 1/2 spins. In contrast to 1, the χ M T values decrease with cooling to 0.13-0.36 emu K mol -1 at 1.9 K, indicating that spins of cobalt atoms align antiparallel to each other. Data fitting using PHI software for the model consisting of three high-spin Co(II) ions and an S = 1/2 radical ligand shows very large Co II -L˙ 3- coupling for 2 and 3 with J 1 values of -442 and -349 cm -1 . The Co II -Co II coupling via the ligand ( J 2 ) is also large, being -100 and -84 cm -1 , respectively, which is more than 10 times larger than that of 1. One of the reasons for the J 2 increase may be the shortening of the Co-N(L) bonds in 3 and 2 to 2.02(2) and 1.993(12) Å. DFT calculations support the population of the quartet state for the Co 3 system, whereas the high-spin decet ( S = 9/2) state is positioned higher by 680 cm -1 and is not populated at 300 K. This is explained by the large Co II -Co II coupling. Thus, a balance between J 1 and J 2 couplings provides parallel or antiparallel alignment of the Fe II and Co II spins, leading to high- or low-spin ground states of {L·[M II (Hal) 2 ] 3 } 3- .

The stepwise reduction of copper(II) 1,4,8,11,15,18,22,25-octafluoro-2,3,9,10,16,17,23,24-octakisperfluoro(isopropyl) phthalocyanine (Cu II F 64 Pc) in o -dichlorobenzene (C 6 H 4 Cl 2 ) by potassium graphite in the presence of cryptand(K + ), abbreviated L + , results in the formation of (L + )[Cu II (F 64 Pc •3- )] - ·2C 6 H 4 Cl 2 ( 1 ), (L + ) 2 [Cu II (F 64 Pc 4- )] 2- ·C 6 H 4 Cl 2 ( 2 ), and (L + ) 2 [Cu II (F 64 Pc 4- )] 2- ( 3 ) complexes. Single-crystal X-ray structures revealed their composition and a monotonic increase with increased phthalocyanine (Pc) negative charges of the magnitude of alternative shortening and elongation of the prior equivalent N meso -C bonds. The complexes are separated by bulky i- C 3 F 7 substituents, large cryptand counterions, and solvent molecules. Weak, new bands are generated in the visible and near-infrared (NIR) domains upon reductions. The one-electron reduced complex, [Cu II (F 64 Pc •3- )] - , is a diradical, exhibiting broad electron paramagnetic resonance (EPR) signals, with intermediate parameters between those typical to Cu II and F 64 Pc •3- . The two-electron reduced complexes, [Cu II (F 64 Pc 4- )] 2- , contain a diamagnetic F 64 Pc 4- macrocycle and a single spin, S = 1/2, on Cu II . The bulky perfluoroisopropyl groups are suppressing intermolecular π-π interactions between Pcs in the [Cu II (F 64 Pc n - )] ( n -2)- ( n = 3, 4) anions, 1 - 3 , similar to the case of the nonreduced complex. However, π-π interactions between 1 and o -dichlorobenzene are observed. The d 9 and Pc electrons in 1 are antiferromagnetically coupled, J = -0.56 cm -1 , as revealed by superconducting quantum interference device (SQUID) magnetometry, but the coupling is at least 1 order of magnitude smaller compared with the coupling observed for Cu II (F 8 Pc •3- ) and Cu II (F 16 Pc •3- ), a testimony to the F accretion effect of rendering the Pc macrocycle progressively more electron-deficient. The data for Cu II (F 64 Pc) provide structural, spectroscopic, and magnetochemical insights, which establish a trend of the effects of fluorine and charge variations of fluorinated Pcs within the macrocycle series Cu II (F x Pc), x = 8, 16, 64. Diamagnetic Pcs might be useful for photodynamic therapy (PDT) and related biomedical applications, while the solvent-processable biradicalic nature of the monoanion salts may constitute the basis for designing robust, air-stable electronic, and magnetically condensed materials.

The interaction of {Cryptand(K + )}(C 60 •- ) with Fe 3 (CO) 12 produced {Cryptand(K + )} 2 {Fe(CO) 2 - μ 2 - η 2 , η 2 -C 60 } 2 2- ·2.5C 6 H 4 Cl 2 ( 1 ) as the first negatively charged iron-bridged fullerene C 60 dimer. The bridged iron atoms are coordinated to two 6-6 bonds of one C 60 hexagon with short and long C(C 60 )-Fe bonds with average lengths of 2.042(3) and 2.088(3) Å. Fullerenes are close to each other in the dimer with a center-to-center interfullerene distance of 10.02 Å. Optical spectra support the localization of negative electron density on the Fe 2 (CO) 4 units, which causes a 50 cm -1 shift of the C≡O vibration bands to smaller wavenumbers, and the C 60 cages. Dimers are diamagnetic and electron paramagnetic resonance silent and have a singlet ground state resulting from the formation of an Fe-Fe bond in the dimer with a length of 2.978(4) Å. According to density functional theory calculations, the excited triplet state is higher than the ground state by 6.5 kcal/mol. Compound 1 shows a broad near-infrared band with a maximum at 970 nm, which is attributable to the charge transfer from the orbitals localized mainly on iron atoms to the C 60 ligand.

A new promising method for the preparation of crystalline 2D polymers based on tetra(4-pyridyl)porphyrin has been developed. Radical anion {H 2 T(4-Py)P˙ - } species are used as the starting material. A new solid-state supramolecular array [{H 2 T(4-Py)P}·{Tb III (TMHD) 3 } 2 ]·2.84C 6 H 14 (1) in which porphyrin units are bridged with Tb III ions to form a self-assembled 2D polymer has been obtained. The complex contains neutral porphyrin macrocycles, which is supported by optical and magnetic data. High-spin paramagnetic Tb III ions are weakly antiferromagnetically coupled in accordance with rather long distances between them.

The reaction of Mn II Pc, Fe II Pc or Fe II PcCl 16 with KCN in the presence of cryptand[2.2.2] yielded dicyano-complexes {cryptand(K + )} 2 {M II (CN) 2 (macrocycle 2- )} 2- · X C 6 H 4 Cl 2 (M = Mn and Fe, X = 1 and 2) that were used for the preparation of trinuclear assemblies of the general formula {cryptand(K + )} 2 {M II (CN) 2 Pc·(ML) 2 } 2- · n C 6 H 4 Cl 2 (M II = Mn II and Fe II ; n = 1, 4 and 5). These assemblies were formed via coordination of two manganese(II) acetylacetonate (ML = Mn II (acac) 2 , S = 5/2), tris(cyclopentadienyl)gadolinium (ML = Cp 3 Gd III , S = 7/2) or tris(cyclopentadienyl)neodymium (ML = Cp 3 Nd III , S = 3/2) units to the nitrogen atoms of bidentate cyano ligands. The N(CN)-Mn{Mn II (acac) 2 } bond is 2.129(3) Å long but the bonds are elongated to 2.43-2.49 Å for tris(cyclopentadienyl)lanthanides. {Cryptand(K + )} 2 {Mn II (CN) 2 Pc·(Mn II (acac) 2 ) 2 } 2- ·5C 6 H 4 Cl 2 (2) contains three Mn(II) ions in different spin states ( S = 5/2 and 1/2). Strong antiferromagnetic coupling of spins observed between them with the exchange interaction ( J ) of -17.6 cm -1 enables the formation of a high S = 9/2 spin state for {Mn II (CN) 2 Pc·(Mn II (acac) 2 ) 2 } 2- dianions at 2 K. The estimated exchange interaction between Mn II ( S = 1/2) and Gd III ( S = 7/2) spins in {Mn II (CN) 2 Pc·(Cp 3 Gd III ) 2 } 2- is only -1.1 cm -1 , and in contrast to 2, nearly independent Gd III and Mn II centers are formed. As a result, no transition to the high-spin state is observed in {Mn II (CN) 2 Pc·(Cp 3 Gd III ) 2 } 2- . The {Mn II (CN) 2 Pc·(Cp 3 Nd III ) 2 } 2- and{Fe II (CN) 2 Pc·(Cp 3 Nd III ) 2 } 2- dianions with Cp 3 Nd III show a decrease of χ M T values in the whole studied temperature range (300-1.9 K). A similar behaviour was found previously for pristine Cp 3 Nd III and Cp 3 Nd III ·L complexes (L = alkylisocyanide ligand).

Hexaazatrianthracene (HATA) and hexaazatriphenylenehexacarbonitrile {HAT(CN) 6 } are reduced by metallic iron in the presence of crystal violet (CV + )(Cl - ). Anionic ligands are produced, which simultaneously coordinate three Fe II Cl 2 to form (CV + ) 2 {HATA ⋅ (Fe II Cl 2 ) 3 } 2-  ⋅ 3 C 6 H 4 Cl 2 (1) and (CV + ) 3 {HAT(CN) 6. (Fe II Cl 2 ) 3 } 3-  ⋅ 0.5CVCl ⋅ 2.5 C 6 H 4 Cl 2 (2). High-spin (S=2) Fe II atoms in both structures are arranged in equilateral triangles at a distance of 7 Å. An antiferromagnetic exchange is observed between Fe II in {HATA ⋅ (Fe II Cl 2 ) 3 } 2- (1) with a Weiss temperature (Θ) of -80 K, the PHI estimated exchange interaction (J) is -4.7 cm -1 . The {HAT(CN) 6  ⋅ (Fe II Cl 2 ) 3 } 3- assembly is obtained in 2. The formation of HAT(CN) 6 .3- is supported by the appearance of an intense EPR signal with g=2.0037. The magnetic behavior of 2 is described by a strong antiferromagnetic coupling between the Fe II and HAT(CN) 6 .3- spins with J 1 =-164 cm -1 (-2 J formalism) and by a weaker antiferromagnetic coupling between the Fe II spins with J 2 =-15.4 cm -1 . The stronger coupling results in the spins of the three Fe II Cl 2 units to be aligned parallel to each other in the assembly. As a result, an increase of the χ M T values is observed with the decrease of temperature from 9.82 at 300 K up to 15.06 emu ⋅ K/mol at 6 K, and the Weiss temperature is also positive being at +23 K. Thus, a change in the charge and spin state of the HAT-type ligand to ⋅3 - results in ferromagnetic alignment of the Fe II spins, yielding a high-spin (S=11/2) system. DFT calculations showed that, due to the high symmetry and nearly degenerated LUMO of both HATA and HAT(CN) 6 , their complexes with Fe II Cl 2 have a variety of closely lying excited high-spin states with multiplicity up to S=15/2., (© 2022 Wiley-VCH GmbH.)

Coordination of tin(II) phthalocyanine to transition metal carbonyl clusters in neutral {Sn II (Pc 2- )} 0 or radical anion {Sn II (Pc˙ 3- )} - states is reported. Direct interaction of Co 4 (CO) 12 with {Sn II (Pc 2- )} 0 yields a crystalline complex {Co 4 (CO) 11 ·Sn II (Pc 2- )} (1). There is no charge transfer from the cluster to phthalocyanine in 1, which preserves the diamagnetic Pc 2- macrocycle. The Ru 3 (CO) 12 cluster forms complexes with one or two equivalents of {Sn II (Pc˙ 3- )} - to yield crystalline {Cryptand[2.2.2](Na + )}{Ru 3 (CO) 11 ·Sn II (Pc˙ 3- )} - (2) or {Cryptand[2.2.2](M + )} 2 {Ru 3 (CO) 10 ·[Sn II (Pc˙ 3- )] 2 } 2- ·4C 6 H 4 Cl 2 (3) (M + is K or Cs). Paramagnetic {Sn II (Pc˙ 3- )} - species in 2 are packed in π -stacking [{Sn II (Pc˙ 3- )} - ] 2 dimers, providing strong antiferromagnetic coupling of spins with exchange interaction J / k B = -19 K. Reduction of Ru 3 (CO) 12 , Os 3 (CO) 12 and Ir 4 (CO) 12 clusters by decamethylchromocene (Cp* 2 Cr) and subsequent oxidation of the reduced species by {Sn IV Cl 2 (Pc 2- )} 0 yield a series of complexes with high-spin Cp* 2 Cr + counter cations ( S = 3/2): (Cp* 2 Cr + ){Ru 3 (CO) 11 ·Sn II (Pc˙ 3- )} - ·C 6 H 4 Cl 2 (4), (Cp* 2 Cr + ){Os 3 (CO) 10 Cl·Sn II (Pc˙ 3- )} - ·C 6 H 4 Cl 2 (5) and (Cp* 2 Cr + ){Ir 4 (CO) 11 ·Sn II (Pc˙ 3- )} 2 - (6). It is seen that reduced clusters are oxidized by Sn IV , which is transferred to Sn II , whereas the Pc 2- macrocycle is reduced to Pc˙ 3- . In the case of Os 3 (CO) 12 , oxidation of the metal atom in the cluster is observed to be accompanied by the formation of Os 3 (CO) 10 Cl with one Os I center. Rather weak magnetic coupling is observed between paramagnetic Cp* 2 Cr + and {Sn II (Pc˙ 3- )} - species in 4, but this exchange interaction is enhanced in 5 owing to Os 3 (CO) 10 Cl clusters with paramagnetic Os I ( S = 1/2) also being involved in antiferromagnetic coupling of spins. The formation of {Sn II (Pc˙ 3- )} - with radical trianion Pc˙ 3- macrocycles in 2-5 is supported by the appearance of new absorption bands in the NIR spectra and essential N meso -C bond alternation in Pc (for 3-5). On the whole, this work shows that both diamagnetic {Sn II (Pc 2- )} 0 and paramagnetic {Sn II (Pc˙ 3- )} - ligands substitute carbonyl ligands in the transition metal carbonyl clusters, forming well-soluble paramagnetic solids absorbing light in the visible and NIR ranges.

The reduction of metal(II) tetraphenylporphyrins, where metal(II) is copper, nickel or iron, has been performed in toluene solution in the presence of a cryptand. Cesium anthracenide was used as a reductant. Crystalline salts {cryptand(Cs + )} 2 {Cu II (TPP 4- )} 2- (1) and {cryptand(Cs + )}{Ni I (TPP 2- )} - ·C 6 H 5 CH 3 (2) have been obtained. The two-electron reduction of {Cu II (TPP 2- )} 0 is centered on the macrocycle allowing one to study for the first time the structure and properties of the TPP 4- tetraanions in the solid state. Tetraanions have a diamagnetic state and show essential C-C meso bond alternation. New bands attributed to TPP 4- appear at 670, 770 and 870 nm. Unpaired S = 1/2 spin is localized on Cu II . The one-electron reduction of {Ni II (TPP 2- )} 0 centered on nickel provides the formation of {Ni I (TPP 2- )} - with unpaired S = 1/2 spin localized on Ni I at 100(2) K. The effective magnetic moment of 2 is 1.68 μ B at 120 K and a broad asymmetric EPR signal characteristic of Ni I is observed for 2 and also for (Bu 3 MeP + ){Ni I (TPP 2- )} - ·C 6 H 5 CH 3 (3) in the 4.2-120 K range. Since dianionic TPP 2- macrocycles are present at 100(2) K, no alternation of C-C meso bonds is observed in 2. The excited quartet S = 3/2 state according to the calculations is positioned close to the ground S = 1/2 state. In the excited state, charge transfer from Ni I to the macrocycle takes place resulting in the formation of Ni II with S = 1 and TPP˙ 3- with S = 1/2 in the {Ni II (TPP˙ 3- )} - anions. Therefore, the increase in the magnetic moment of 2 above 150 K is attributed to the population of the excited quartet state with a gap of 750 K. Salt 2 is EPR silent above 150 K and manifests absorption bands characteristic of TPP˙ 3- at RT. The reduction of Ni II (TPP 2- ) and Fe II (TPP 2- ) by cesium anthracenide in the presence of Bu 3 MeP + yields crystals of 3 and (Bu 3 MeP + ){Fe I (TPP 2- )} - ·C 6 H 5 CH 3 (4) whose crystal structures and optical properties are also presented. DFT calculations have been carried out for {M II (TPP 2- )} (M = Cu, Ni and Fe) and their anions to interpret the experimental results obtained for 1-4.

Metal complexes of trithiadodecaazahexaphyrin (Hhp) that contain M II 3 O clusters inside a π-extended trianionic (Hhp 3- ) macrocycle have been prepared. Studies of the magnetic properties of Ni II 3 O(Hhp) and Cu II 3 O(Hhp) reveal a diamagnetic and EPR-silent trianionic (Hhp 3- ) macrocycle and diamagnetic Ni II 3 (O 2- ) or paramagnetic Cu II 3 (O 2- ) tetracations. The positive charge of M II 3 O(Hhp) is compensated by one acetate anion {M II 3 O(Hhp)} + (CH 3 CO 2 - ). The three-electron reduction of {M II 3 O(Hhp)} + yields {cryptand(Cs + )} 2 {Ni II 2 Ni I O(Hhp 5- )} 2- ·2C 7 H 8 ( 1 ) and {cryptand(Cs + )} 2 {Cu II 3 O(Hhp •6- )} 2- ·C 7 H 8 ( 2 ) crystalline salts. The magnetic properties of 1 reveal the formation of Hhp 5- and the reduction of nickel(II) to the paramagnetic Ni I ion ( S = 1/2), which is accompanied by the formation of the {Ni II 2 Ni I O(Hhp 5- )} 2- dianion. As a result, the magnetic moment of 1 is 1.68 μ B in the 20-220 K range, and a broad EPR signal of Ni I was observed. The Hhp 5- macrocycle has a singlet ground state, but the increase in the magnitude of the magnetic moment of 1 above 220 K is attributed to the population of the triplet excited state in Hhp 5- . The {Ni II 2 Ni I O(Hhp 5- )} 2- dianion is transferred from the doublet excited state to the quartet excited state with an energy gap of 1420 ± 50 K. Salt 1 also shows an unusually strong low-energy NIR absorption, which was observed at 1000-2200 nm. In 2 , a highly reduced Hhp •6- radical hexaanion ( S = 1/2) coexists with a Cu II 3 (O 2- ) cluster ( S = 1/2) in the {Cu II 3 O(Hhp •6- )} 2- dianions. The dianions have a triplet ground state with antiferromagnetic exchange between two S = 1/2 spins with J = -6.4 cm -1 . The reduction of Hhp in both salts equalizes the initially alternated C-N bonds, supporting the increase in the Hhp macrocycle electron delocalization.

Crystalline {Cryptand[2.2.2](Na + )}{HAT(CN) 6 .- }⋅0.5C 6 H 4 Cl 2 (1), {Cryptand[2.2.2](K + )}{HAT(CN) 6 .- } (2), (CV + ){HAT(CN) 6 .- } (3), and (CV + ){HAT(CN) 6 .- }⋅2C 6 H 4 Cl 2 (4) salts (where CV + is the crystal violet cation) containing hexaazatriphenylenehexacarbonitrile radical anions have been obtained. The solid-state molecular structure as well as the optical and magnetic properties of HAT(CN) 6 .- are studied. The formation of HAT(CN) 6 .- in 1-4 leads to the appearance of new bands in the visible range, at 694 and 740 nm. The HAT(CN) 6 .- radical anions have spin state S=1/2 and are packed in one-dimensional stacks containing the {HAT(CN) 6 .- } 2 dimers alternated with weaker interacting pairs of HAT(CN) 6 .- in 1 and nearly isolated {HAT(CN) 6 .- } 2 dimers in 2. The {HAT(CN) 6 .- } 2 dimers are diamagnetic in 1 but they effectively mediate one-dimensional antiferromagnetic coupling of spins within the stacks with moderate exchange interaction of J/k B = -80 K. The behaviour of salt 2 is described by a singlet-triplet model for the {HAT(CN) 6 .- } 2 dimers with an energy gap of 434(±7) K. Magnetic behaviour of both salts agree well with the data of extended Hückel calculations. Salts 3 and 4 contain isolated stacks of alternated HAT(CN) 6 .- and CV + ions, and in this case, nearly paramagnetic behaviour is observed with Weiss temperatures of -1 and -7 K, respectively. Narrow Lorentzian EPR signals with g = 2.0033-2.0039 were found for the HAT(CN) 6 .- radical anions in 1 and 4 but in solution g-factor shifts to 1.9964. The electronic structure of HAT(CN) 6 .- is analysed based on X-ray diffraction data for 2, showing a Jahn-Teller distortion of the radical anion that reduces the symmetry from D 3h to C s and splits the initially degenerated LUMOs., (© 2020 Wiley-VCH GmbH.)

The reaction of GaIIIClPc, SnIVCl2TPP and BIIIClSubPc containing phthalocyanine (Pc), tetraphenylporphyrin (TPP) and subphthalocyanine (SubPc) macrocycles with cyanide in the presence of cryptand[2.2.2] under anaerobic conditions yields crystalline salts in which cyano anions substitute chloride anions at GaIII, SnIV or BIII, as well as reducing the macrocycles or adding one or two CN- to them. The reaction of GaIIICl(Pc2-) with CN- yields {crypt(K+)}{GaIIICN(Pc˙3-)}˙-·0.5C6H4Cl2 (1) in which the Pc2- macrocycle is reduced to Pc˙3-. Such reduction could probably occur through the addition of CN- to Pc2- forming {GaIII(CN)[Pc(CN)]3-}- which can decompose further interacting with an excess of CN-. As a result, Pc˙3- and cyanogene anions are formed. The interaction of SnIVCl2(TPP2-) with CN- is accompanied by the addition of CN- to the meso-carbon atom of porphyrin forming diamagnetic TPP(CN)3- macrocycles in {crypt(K+)}{SnIV(CN)2[TPP(CN)]3-}- (2). Salt 2 shows a strong NIR absorption band with the maximum at 854 nm whose intensity is comparable with that of the Soret band. The interaction of BIIICl(SubPc2-) with three equivalents of CN- is accompanied by the addition of two CN- to carbon atoms of SubPc2- closest to meso-nitrogen atoms forming {BIII(CN)[SubPc(CN)2]4-}2-. Most probably these dianions transfer electrons to C6H4Cl2 producing the {BIII(CN)[SubPc(CN)2]˙3-}˙- radical anions which form σ-bonded diamagnetic dianions in {crypt(K+)}2{BIII(CN)[SubPc(CN)2]}22-·3C6H4Cl2 (3). The remaining carbon atom closest to the meso-nitrogen atom is involved in this dimerization. According to the calculations, the energy of the C-CN bond is minimal for {GaIII(CN)[Pc(CN)]3-}- enabling further transformation of these anions to {GaIIICN(Pc˙3-)}˙- in 1, whereas cyano-containing anions in 2 and 3 with higher energy of this bond are stable towards the elimination of CN. Optical and magnetic properties of 1-3 together with their crystal and molecular structures are presented. The possible ways of the formation of 1-3 are discussed based on DFT calculations.

The reduction of copper(ii) octafluoro- {CuII(F8Pc)} and hexadecafluorophthalocyanines {CuII(F16Pc)} by NaCpCo(CO)2 in the presence of cryptand[2.2.2] yields new crystalline {cryptand(Na+)}[CuII(F8Pc)˙3-]-·2C6H4Cl2 (1) and {cryptand(Na+)}2[CuII(F16Pc)4-]2-·C6H14 (2) salts. Together with two previously characterized salts of CuII(FxPc) (x = 8 and 16), this allows the study of the molecular structure and optical and magnetic properties of fluorinated copper phthalocyanines in different reduction states (-1 and -2). The blue shift of the Q-band increases together with the negative charge on the macrocycle, and new weak bands of the anions appear at 820-1013 nm. Alternation of the Nmeso-C bonds manifests itself in reduced macrocycles due to a partial disruption of macrocycle aromaticity. In the case of CuII(F8Pc) this effect is nearly two times stronger for dianions than for monoanions. The alternation of the bonds is less pronounced for perfluorinated CuII(F16Pc)n- (n = 1, 2) anions most probably due to a partial delocalization of the negative charge on fluoro-substituents. The reduction also noticeably elongates the average C-F bonds in CuII(F8Pc). The first reduction centered on the macrocycle leads to the formation of [CuII(F8Pc)˙3-]- in 1 with two S = 1/2 spins positioned on CuII and the radical trianion (F8Pc)˙3- macrocycle. As a result, a broad EPR signal is observed with g = 2.1652 at RT attributable to both paramagnetic species having exchange interactions. The formation of dimerized stacks from [CuII(F8Pc)˙3-]- in 1 results in strong enough magnetic coupling of the (F8Pc)˙3- spins within the dimers (J/kB = -21.8 cm-1), and weaker intramolecular coupling is observed between CuII and (F8Pc)˙3- (J/kB = -10.8 cm-1). Coupling between (F8Pc)˙3- spins from the neighboring dimers is nearly 1.5 times weaker (-14.6 cm-1). Under reduction conditions, a second electron also comes to the macrocycle forming diamagnetic F16Pc4- tetraanions. In this case S = 1/2 spin is preserved on CuII. Magnetic coupling between these centers is weak due to the long distances between them in the [CuII(F8Pc)4-]2- chains of 2. Salt 2 shows an EPR signal with a HF splitting characteristic of CuII with g∥ = 2.1806 (A∥ = 20.11 mT), and g⊥ = 1.9597 at RT.

Two salts of the aromatic hydrocarbon decacyclene, {cryptand[2.2.2](Cs + )} (decacyclene .- ) (1) and {Bu 3 MeP + }(decacyclene .- ) (2), were obtained. In both salts, decacyclene .- radical anions formed channels occupied by cations. However, corrugated hexagonal decacyclene .- layers could be outlined in the crystal structure of 1 with several side-by-side C⋅⋅⋅C approaches. The decacyclene .- radical anions showed strong distortion in both salts, deviating from the C 3 symmetry owing to the repulsion of closely arranged hydrogen atoms and the Jahn-Teller effect. Radical anions showed intense unusually low energy absorption in the IR-range, with maxima at 4800 and 6000 cm -1 . According to the carculations, these bands can originate from the SOMO-LUMO+1 and SOMO-LUMO+2 transitions, respectively. Radical anions exhibited a S=1/2 spin state, with an effective magnetic moment of 1.72 μ B at 300 K. The decacyclene .- spin antiferromagnetically coupled with a Weiss temperature of -11 K. Spin ordering was not observed down to 1.9 K owing to spin frustration in the hexagonal decacyclene .- layers., (© 2020 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.)

A first coordination {[2.2.2]cryptand(K+)}2{FeII(TI˙-)(TI2-)}2·2C6H4Cl2 (1) complex of iron(ii) containing radical anions and dianions of thioindigo (TI) was obtained. The complex has two high-spin FeII centers bound by two oxygen atoms, and the TI˙- radical anions are coordinated to each FeII. As a result, the 4-spin system consisting of TI˙- (S = 1/2)-FeII (S = 2)-FeII (S = 2)-TI˙- (S = 1/2) coupled spins is formed within a dimer with strong FeII-FeII (J = -51.1 cm-1) and weaker FeII-TI˙- interactions of (J = -35.4 cm-1).

Reduction of {Zn II (TPyP)} to the {Zn II (TPyP)} 2- dianions (TPyP: tetra(4-pyridyl)porphyrin) in the presence of Bu 3 MeP + allows one to observe the C-H bond cleavage in the methyl group of Bu 3 MeP + to form (Bu 3 MeP + ){Zn II (CH 2 PBu 3 )(TPyPH)} - ·0.337C 6 H 5 CH 3 ( 1 ). Salt 1 is the first coordination complex of neutral CH 2 PBu 3 ylide and metalloporphyrin. The released hydrogen atom attacks the meso -carbon atom of TPyP 4- forming a TPyPH 3- macrocycle related to phlorins. Decreased symmetry of the TPyPH 3- allows the observation of a strong NIR absorption. We discuss the molecular structure, optical, and magnetic properties of 1 together with its formation pathways.

Reduction of free-base [30]trithia-2,3,5,10,12,13,15,20,22,23,25,30-dodecaazahexaphyrin (H 3 Hhp) yields {cryptand[2.2.2](K)} 2 {(K)(H 3 Hhp) 2 }⋅4C 6 H 4 Cl 2 (1) containing double-decker {(K)(H 3 Hhp) 2 } ⋅2- radical dianions, whose structure was elucidated using X-ray diffraction. Potassium ion forms 12 short (K + )⋅⋅⋅N(H 3 Hhp) contacts with two H 3 Hhp macrocycles in the 3.048-3.157 Å range. Dianions have S=1/2 spin state manifesting an effective magnetic moment of 1.64 μ B at 300 K and a narrow Lorentzian electron paramagnetic resonance signal. Quantum chemical calculations support the ionic nature of the (K + )-N(H 3 Hhp) interactions and the nearly equal distribution of the -1.5 charge over each macrocycle. H 3 Hhp takes the role of an aza-crown ether in free-base reduced state and forms a new type of double-decker complex., (© 2020 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.)

A series of compounds with Sc 3 N@I h -C 80 in the neutral, monomeric, and dimeric anion states have been prepared in the crystalline form and their molecular structures and optical and magnetic properties have been studied. The neutral Sc 3 N@I h -C 80 ⋅3 C 6 H 4 Cl 2 (1) and (Sc 3 N@I h -C 80 ) 3 (TPC) 2 ⋅5 C 6 H 4 Cl 2 (2, TPC=triptycene) compounds both crystallized in a high-symmetry trigonal structure. The reduction of Sc 3 N@I h -C 80 to the radical anion resulted in dimerization to form diamagnetic singly bonded (Sc 3 N@I h -C 80 - ) 2 dimers. In contrast to {[2.2.2]cryptand(Na + )} 2 (Sc 3 N@I h -C 80 - ) 2 ⋅2.5 C 6 H 4 Cl 2 (3) with strongly disordered components, we synthesized new dimeric phases {[2.2.2]cryptand- (K + )} 2 (Sc 3 N@I h -C 80 - ) 2 ⋅2 C 6 H 4 Cl 2 (4) and {[2.2.2]cryptand- (Cs + )} 2 (Sc 3 N@I h -C 80 - ) 2 ⋅2 C 6 H 4 Cl 2 (5) in which only one major dimer orientation was found. The thermal stability of the (Sc 3 N@I h -C 80 - ) 2 dimers was studied by EPR analysis of 3 to show their dissociation in the 400-460 K range producing monomeric Sc 3 N@I h -C 80 .- radical anions. This species shows an EPR signal with a hyperfine splitting of 5.8 mT. The energy of the intercage C-C bond was estimated to be 234±7 kJ mol -1 , the highest value among negatively charged fullerene dimers. The EPR spectra of crystalline (Bu 3 MeP + ) 3 (Sc 3 N@I h -C 80 .- ) 3 ⋅C 6 H 4 Cl 2 (6) are presented for the first time. The salt shows an asymmetric EPR signal, which could be fitted by three lines. Two lines were attributed to Sc 3 N@I h -C 80 .- . Hyperfine splitting is manifested above 180 K due to the hyperfine interaction of the electron spin with the three scandium atoms (a total of 22 lines with an average splitting of 5.32 mT are observed at 220 K). Furthermore, each of the 22 lines is additionally split into six lines with an average separation of 0.82 mT. The large splitting indicates intrinsic charge and spin density transfer from the fullerene cage to the Sc 3 N cluster. Both the monomeric and dimeric Sc 3 N@I h -C 80 - anions show an intrinsic shift of the IR bands attributed to the Sc 3 N cluster and new bands corresponding to these species appear in the NIR range of their UV/Vis/NIR spectra, which allows these anions to be distinguished from neutral species., (© 2019 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.)

Radical anion salt {cryptand[2.2.2] (K + )} 2 (bispheroid) 2- ⋅3.5C 6 H 4 Cl 2 (1) of the double-caged fullerene C 60 derivative, in which fullerene cages are linked by a cyclobutane bridging cycle and additionally by a pyrrolizidine moiety, was obtained. Each fullerene cage in this derivative accepts one electron on reduction, thus forming the (bispheroid) 2- dianions with two interacting S=1/2 spins on the neighboring cages. Low-temperature magnetic measurements reveal a singlet ground state of the bispheroid dianions whereas triplet contributions prevail at increased temperature. An estimated exchange interaction between two spins J/k B =-78 K in 1 indicates strong magnetic coupling between them, nearly two times higher than that (J/k B =-44.7 K) in previously studied (C 60 - ) 2 dimers linked via a cyclobutane bridge only. The enhancement of magnetic coupling in 1 can be explained by a shorter distance between the fullerene cages and, possibly, an additional channel for the magnetic exchange provided by a pyrrolizidine bridge. Quantum-chemical calculations of the lowest electronic state of the dianions by means of multi-configuration quasi-degenerate perturbation theory support the experimental findings., (© 2019 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.)

Reduction of terbium(III) double-decker phthalocyanine, Tb III Pc 2 (1), by sodium fluorenone ketyl in the presence of bis(triphenylphosphoranylidene)ammonium cations yields one-electron-reduced (PPN + ){Tb III (Pc 2- ) 2 } - ·2.5C 6 H 4 Cl 2 (2) containing the dianionic Pc 2- macrocycles, whereas a stronger NaCpCo(CO) 2 reductant in the presence of an excess of cryptand yields two-electron-reduced {Cryptand(Na + )} 2 {(Pc 2- )Tb III (Pc •3- )} 2- (3) containing the Pc •3- radical trianionic macrocycle. Isolated pairs of the {Tb III (Pc 2- ) 2 } - anions are formed in 2, whereas compound 3 has unique 3D packing of the macrocycles with weak π-orbitals overlapping in all three directions. This is the first example of the two-electron-reduced lanthanide double-decker containing Pc •3- radical trianion studied in solid state. Compound 2 manifests single-ion magnet (SIM) behavior with a large effective spin-reversal energy barrier of U eff = 538 cm -1 in comparison with previously studied (Bu 4 N + ){Tb III (Pc 2- ) 2 } - ( U eff = 230 cm -1 ). Thus, changes in cation size and shape affect the molecular packing of {Tb III (Pc 2- ) 2 } - and increase the spin-reversal energy barrier. At the same time, two-electron-reduced species 3 containing Tb III and Pc •3- show no signs of SIM such as hysteresis loop at 1.9 K, and no peaks are observed on the temperature dependencies of in-phase (χ') and out-of-phase (χ″) signals. In contrast to EPR silent 2, both compounds 1 and 3 manifest broad signals from paramagnetic Tb III ions. Narrower signals attributed to Pc •3- are of high intensity only in 3. In addition to the absorption bands of Pc in the UV and visible spectral range, compound 3 manifests the lowest energy absorption band in solid-state spectra even in the near IR range at 4700 cm -1 (2130 nm), whereas such bands are not observed in the spectrum of 2. These data show that the reduction of the Pc macrocycles in the lanthanide double-deckers leads to the appearance of new very low-energy new transitions associated with Pc •3- whose energy is the lowest among known reduced metal phthalocyanines.

A series of anionic coordination complexes of tin(ii) phthalocyanine (Pc) with cyanide, cyanate, and imidazolate (Im) anions (1, 3, and 4, respectively) and tin(ii) naphthalocyanine (Nc) with cyanide anions (2) has been obtained. Two anions coordinate to tin(ii) atoms in 1-4 to form the {SnL2Mac}2- dianions in salts with the general formula {crypt[2.2.2](M+)}2{SnL2Mac}2- (M = K or Na; Mac: Pc or Nc; L = CN-, OCN-, Im-). The coordination of two ligands to SnII stabilizes these atoms in the higher tin(iv) oxidation state, providing transfer of two electrons from SnII to the macrocycle. The formation of tetraanionic (4-) macrocycles is accompanied by the appearance of new absorption bands in the NIR range, essentially blue-shifting both Soret and Q bands, and noticeable distortion in the macrocycles in 2-4, showing alternation of the C-C and C-N bonds. However, such distortions are not observed in 1. The absence of alternation in the case of 1 can be explained by the effect of uncompensated electric field from the surrounding cations, which stabilizes the macrocycle configuration with aligned bonds but nonuniform negative charge distribution on the imine nitrogen atoms. The cyanide ligand coordinates to SnPc by a nitrogen atom in 1, forming a Sn-N bond of 2.339(1) Å in length, whereas the cyanide ligand coordinates to SnNc by a carbon atom in 2, forming a shorter Sn-C bond of 2.266(3) Å in length. DFT calculations support the reorientation of the CN ligand in 1, which is induced by the electrostatic field of closely located cations.

Salts of fullerene C60˙- and endometallofullerene Sc3N@Ih-C80˙- radical anions with Bu3MeP+ cations ((Bu3MeP+)3(C60˙-)3·C6H4Cl2 (1) and (Bu3MeP+)3(Sc3N@Ih-C80˙-)3·C6H4Cl2 (2)) have been obtained. The C3 symmetry of the Bu3MeP+ cation provides 2D Kagome lattices with an equilateral triangle arrangement of fullerenes in accordance with trigonal crystal symmetry P31m. The C60˙- and Sc3N@Ih-C80˙- radical anions preserve their monomeric forms in 1 and 2 with the S = 1/2 spin state down to 1.9 K. The close packing of the fullerene radical anions results in strong antiferromagnetic coupling of the spins with Weiss temperatures of -108 K for 1 and -43 K for 2. Compound 1 is a rare example of a magnetic system in which in spite of the strong magnetic coupling of spins no long-range ordering is observed down to 1.9 K. The 13C NMR spectra of the 13C enriched sample of 1 support the absence of the antiferromagnetic ordering of spins down to 1.5 K. Thus, the crystals of 1 preserve large spin frustration forced by the trigonal symmetry. Therefore, compound 1 is a promising candidate for the first observation of a quantum spin liquid (QSL) state in a fullerene-based system. Isostructural salt 2 is the first compound that contains monomeric paramagnetic Sc3N@Ih-C80˙- radical anions stable down to 1.9 K, which show strong spin frustration. These data indicate the ability of endometallofullerenes to give exotic magnetic systems such as QSLs.

Neutral {CpFe II (CO) 2 [Sn II (Pc •3- )]} {Cp is cyclopentadienyl ( 1 , 2 ) or Cp* is pentamethylcyclopentadienyl ( 3 ); Pc: phthalocyanine}, {Cp*Fe II (CO) 2 [Sn II (Nc •3- )]} ( 4 , Nc: naphthalocyanine), and {CpFe II (CO) 2 [Sn II (TPP •3- )]} ( 5 , TPP: tetraphenylporphyrin) complexes in which CpFe II (CO) 2 fragments (Cp: Cp or Cp*) are coordinated to Sn II (macrocycle •3- ) have been obtained. The product complexes were obtained at the reaction of charge transfer from CpFe I (CO) 2 (Cp: Cp or Cp*) to [Sn II (macrocycle 2- )] to form the diamagnetic Fe II and paramagnetic radical trianionic macrocycles. As a result, these formally neutral complexes contain S = 1/2 spins delocalized over the macrocycles. This provides alternation of the C-N imine or C-C meso bonds in the macrocycles, the appearance of new bands in the near-infrared spectra of the complexes, and blue shift of both Soret and Q-bands. The {CpFe II (CO) 2 Sn II (macrocycle •3- )} units (Cp: Cp or Cp*, macrocycle: Pc or Nc) form closely packed π-stacking dimers in 1 and 3 or one-dimensional chains in 2 and 4 with effective π-π interaction between the macrocycles. Such packing allows strong antiferromagnetic coupling between S = 1/2 spins. Magnetic interaction can be described well by the Heisenberg model for the isolated dimers in 1 and 3 with exchange interaction J / k B = -78 and -85 K, respectively. Magnetic behavior of 2 and 4 is described well by the model that includes contributions from an antiferromagnetically coupled S = 1/2 dimer ( J intra ) and a Heisenberg S = 1/2 chain with alternating antiferromagnetic spin exchange between the neighbors ( J inter ). Compound 2 demonstrates large intradimer interaction of J intra / k B = -54 K and essentially weaker interdimer exchange interactions of J inter / k B = -6 K, whereas compound 4 shows strong magnetic coupling of spins within the dimers ( J intra / k B = -170 K) as well as between the dimers ( J inter / k B = -40 K). Compound {CpFe II (CO) 2 [Sn II (TPP •3- )]} ( 5 ) shows no π-π interactions between the porphyrin macrocycles, and magnetic coupling is weak in this case (Weiss temperature is -5 K). Preparation of a similar complex with indium(III) chloride phthalocyanine yields {CpFe(CO) 2 [In(Pc 2- )]} ( 6 ). In this complex, indium(III) atoms are reduced instead of the phthalocyanine macrocycles that explains electron paramagnetic resonance silence of 6 in the 4-295 K range., Competing Interests: The authors declare no competing financial interest.

In this study, the titanyl and vanadyl phthalocyanine (Pc) salts (Bu 4 N + ) 2 [M IV O(Pc 4- )] 2- (M=Ti, V) and (Bu 3 MeP + ) 2 [M IV O(Pc 4- )] 2- (M=Ti, V) with [M IV O(Pc 4- )] 2- dianions were synthesized and characterized. Reduction of M IV O(Pc 2- ) carried out with an excess of sodium fluorenone ketyl in the presence of Bu 4 N + or Bu 3 MeP + is exclusive to the phthalocyanine centers, forming Pc 4- species. During reduction, the metal +4 charge did not change, implying that Pc is an non-innocent ligand. The Pc negative charge increase caused the C-N(pyr) bonds to elongate and the C-N(imine) bonds to alternate, thus increasing the distortion of Pc. Jahn-Teller effects are significant in the [eg(π*)] 2 dianion ground state and can additionally distort the Pc macrocycles. Blueshifts of the Soret and Q-bands were observed in the UV/Vis/NIR when M IV O(Pc 2- ) was reduced to [M IV O(Pc . 3- )] . - and [M IV O(Pc 4- )] 2- . From magnetic measurements, [Ti IV O(Pc 4- )] 2- was found to be diamagnetic and (Bu 4 N + ) 2 [V IV O(Pc 4- )] 2- and (Bu 3 MeP + ) 2 [V IV O(Pc 4- )] 2- were found to have magnetic moments of 1.72-1.78 μ B corresponding to an S=1/2 spin state owing to V IV electron spin. As a result, two latter salts show EPR signals with V IV hyperfine coupling., (© 2018 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.)

Reduction methods for the preparation of coordination complexes of titanium(IV) and indium(III) phthalocyanines (Pc) with organic dyes such as indigo, thioindigo, and squarylium dye III (SQ) have been developed, which allow one to obtain crystalline {cryptand(K + )}{(cis-indigo-O,O) 2- Ti IV (Pc 2- )}(Cl - )⋅C 6 H 4 Cl 2 (1), {cryptand(K + )}{(cis-thioindigo-O,O) 2- In III (Pc 2- )} - ⋅C 6 H 4 Cl 2 (2), and {cryptand(K + )}{[(SQ) 2 -O,O] 2- In III (Pc 2- )} - ⋅3.5 C 6 H 4 Cl 2 (3) complexes. The formation of these complexes is accompanied by the reduction of the starting dyes to the anionic state. Transition of trans-indigo or trans-thioindigo to the cis conformation in 1 and 2 provides coordination of both carbonyl oxygen atoms of the dye to Ti IV Pc or In III Pc. SQ is reduced to the radical anion state and forms unusual diamagnetic singly bonded (SQ - ) 2 dimers in 3. These dimers have two closely positioned carbonyl oxygen atoms coordinated to In III Pc. Dianionic Pc 2- macrocycles have been found in 1-3. The complexes contain two chromophore molecules at one metal center. However, their optical spectra are defined mainly by absorption bands of the metal phthalocyanines., (© 2018 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.)

N-Methylimidazole (MeIm) solvates of vanadium(ii), chromium(ii) and iron(ii) phthalocyanines: [VII(MeIm)2(Pc2-)]0·MeIm (1) and [MII(MeIm)2(Pc2-)]0·2C6H4Cl2 (M = V (2), Cr (3), and Fe (4)) have been obtained and studied in a crystalline form. It has been shown that central metal atoms have the +2 oxidation state in 1-4 and dianionic Pc2- macrocycles are formed. Optical spectra of 1-3 (VII, CrII) are different from that of 4 (FeII) due to the appearance of intense absorption bands in the NIR range at 1187 nm for 1 and 2 and 1178 nm for 3 and manifestation of multiple bands in the visible range. Absorption in the NIR range is explained by unusually small gaps between the molecular orbitals at around HOMO and LUMO for MeIm solvated CrIIPc and VIIPc. The essential diradicaloid character of the Pc macrocycles in [CrII(MeIm)2(Pc2-)]0, in which α- and β-orbitals are distributed in different regions of the macrocycle, has also been shown. In this case, the diradicaloid character is comparable to that of aromatic hydrocarbon heptacene. Magnetic properties of 1-3 are defined by metal atoms with a S = 3/2 spin state for VII and S = 1 for CrII. Compounds 1-3 manifest broad isotropic EPR signals at 4.2 K with g = 2.0188 and a linewidth (ΔH) of 81.8 mT for 1 (VII), g = 1.8300 and a linewidth ΔH = 161.0 mT for 2 (VII), and g = 2.0534 and ΔH = 60.27 mT for 3 (CrII). These signals shifted to smaller g-factors with the temperature increase. Integral intensity of narrow EPR signals from Pc˙3- does not exceed 0.1% from those of broad signals in 1-3. Complex 4 is EPR silent due to the presence of diamagnetic FeII and Pc2-.

A crystalline {cryptand[2.2.2.](K + )}{H 2 T(4-Py)P •- }·C 6 H 4 Cl 2 (1) salt with tetra(4-pyridyl)porphyrin radical anions was obtained, enabling the effect of reduction on a metal-free porphyrin macrocycle to be studied. In contrast to pristine H 2 T(4-Py)P, the H 2 T(4-Py)P •- radical anions have altered C-C(meso) bonds due to partial loss of aromaticity from the porphyrin macrocycle. Short and long bonds have average lengths of 1.396(3) and 1.426(3) Å, which thus differ by 0.03 Å. Reduction affects the positions of the Soret and Q-bands of porphyrin observed in the spectrum of 1 at 439 and 512, 583, and 614 nm, and new bands of the radical anion appear at 684, 755, and 900 nm. The H 2 T(4-Py)P •- radical anions have a spin state of S = 1/2 and a magnetic moment of 1.64 μ B at 300 K. Salt 1 shows a narrow asymmetric EPR signal fitted with two Lorentzian lines, with g ⊥ = 2.0031 and a line width (ΔH) of 0.186 mT, and g ∥ = 2.0019 (ΔH = 0.284 mT) at 295 K, and this signal splits into three components below 39 K. Salt 1 shows antiferromagnetic spin coupling with a Weiss temperature of -2 K.

The reaction of tin(iv) phthalocyanine dichloride {Sn IV Cl 2 (Pc 2- )} with decamethylmetallocenes (Cp* 2 M, M = Co, Cr) has been studied. Decamethylcobaltocene reduces Sn IV Cl 2 (Pc 2- ) to form the (Cp* 2 Co + ){Sn IV Cl 2 (Pc˙ 3- )}˙ - ·2C 6 H 4 Cl 2 (1) complex. The negative charge of {Sn IV Cl 2 (Pc˙ 3- )}˙ - is delocalized over the Pc macrocycle providing the alternation of the C-N(imine) bonds, the appearance of new bands in the NIR range and a strong blue shift of both the Soret and Q-bands in the spectrum of 1. The magnetic moment of 1 is equal to 1.68μ B at 300 K, indicating the contribution of one S = 1/2 spin of the Pc˙ 3- macrocycles. These macrocycles form closely packed double stacks in 1 with effective π-π interactions providing strong antiferromagnetic coupling of spins at a Weiss temperature of -80 K. Decamethylchromocene initially also reduces Sn IV Cl 2 (Pc 2- ) to form the [(Cp* 2 Cr + ){Sn VI Cl 2 (Pc˙ 3- )}˙ - complex but further reaction between the ions is observed. This reaction is accompanied by the substitution of one Cp* ligand of Cp* 2 Cr by chloride anions originating from {Sn IV Cl 2 (Pc˙ 3- )}˙ - to form the complex {(Cp*CrCl 2 )(Sn IV (μ-Cl)(Pc 2- ))}·C 6 H 4 Cl 2 (2) in which the (Cp*CrCl 2 ) and {Sn IV (Pc 2- )} species are bonded through the μ-bridged Cl - anion. According to the DFT calculations, this reaction proceeds via an intermediate [(Cp* 2 CrCl)(SnClPc)] complex.

A diamagnetic complex, {(cis-indigo-N,N) 2- (Cp*Ir III )} (1), in which deprotonated cis-indigo dianions coordinate an iridium center through two nitrogen atoms was obtained. By employment of the ability of the iridium center in 1 to coordinate an additional ligand, the complex [(Bu 4 N + ) 2 {[Sn II (Pc •3- )](cis-indigo-N,N) 2- Cp*Ir III } •- 2 ·0.5(H 2 Indigo)·2.5C 6 H 4 C l2 (2), which has two functional ligands coordinating an Ir III center, was obtained. This complex has a magnetic moment of 1.71 μ B at 300 K, in accordance with an S = 1/2 spin state. The spin density is mainly delocalized over the Pc •3- macrocycle and partially on (cis-indigo-N,N) 2- . Due to an effective π-π interaction, a thermally activated charge transfer from [Sn II (Pc •3- )] •- to (cis-indigo-N,N) 2- is observed, with an estimated Gibbs energy (-ΔG°) of 9.27 ± 0.18 kJ/mol. The deprotonation of indigo associated with the coordination of Ir III by the indigo releases H + ions, which protonate noncoordinating indigo molecules to produce leuco cis-indigo (H 2 Indigo). One H 2 indigo links two (cis-indigo-N,N) 2- dianions in 2 to produce strong N-H···O═C and O-H···O═C hydrogen-bonding interactions.

Reaction of decamethylchromocene (Cp* 2 Cr) with thioindigo (TI) yields a coordination complex {[TI-(μ 2 -O), (μ-O)]Cp*Cr} 2 ·C 6 H 14 (1) in which one Cp* ligand in Cp* 2 Cr is substituted by TI. TI adopts cis-conformation in 1 allowing the coordination of both carbonyl groups to chromium. Additionally, one oxygen atom of TI becomes a μ 2 -bridge for two chromium atoms to form {[TI-(μ 2 -O), (μ-O)]Cp*Cr} 2 dimers with a CrCr distance of 3.12 Å. According to magnetic data, diamagnetic TI 2- dianions and two Cr 3+ atoms with a high S = 3/2 spin state are present in a dimer allowing strong antiferromagnetic coupling between two Cr 3+ spins with an exchange interaction of -35.4 K and the decrease of molar magnetic susceptibility below 140 K. Paramagnetic TI˙ - radical anions with the S = 1/2 spin state have also been obtained and studied in crystalline {cryptand[2,2,2](Na + )}(TI˙ - ) (2) salt showing that both radical anion and dianion states are accessible for TI.

The reduction of 5,10,15-triphenylcorrole (H 3 TPCor) with decamethylchromocene yields (Cp* 2 Cr + )(H + )(H 2 TPCor˙ 2- )·C 6 H 4 Cl 2 (1). It is accompanied by the deprotonation of H 3 TPCor and the formation of planar H 2 TPCor˙ 2- radical dianions. Complex 1 manifests a band at about 750 nm observed in the solution spectra of H 2 TArylCor˙ 2- and demonstrates an EPR signal attributed to the reduced corrole macrocycle. The magnetic moment of 1 of 4.10μ B at 300 K indicates the contribution of Cp* 2 Cr + (S = 3/2) and H 2 TPCor˙ 2- (S = 1/2). These paramagnetic species alternate in the π-stacks providing rather effective antiferromagnetic coupling of spins at the Weiss temperature of -31 K. To distinguish the H 2 TPC˙ 2- dianions from the deprotonated H 2 TPCor - anions, we also studied the {cryptand[2,2,2](Na + )}(H 2 TPCor - )·0.5C 6 H 4 Cl 2 (2) salt with deprotonated corrole anions. In this case, a planar macrocycle was formed as well. However, the properties of H 2 TPCor - in 2 differ from those of H 2 TPCor˙ 2- in 1.

Reduction of aluminum(III), gallium(III), and indium(III) phthalocyanine chlorides by sodium fluorenone ketyl in the presence of tetrabutylammonium cations yielded crystalline salts of the type (Bu 4 N + ) 2 [M III (HFl-O - )(Pc .3- )] .- (Br - )⋅1.5 C 6 H 4 Cl 2 [M=Al (1), Ga (2); HFl-O - =fluoren-9-olato - anion; Pc=phthalocyanine] and (Bu 4 N + ) [In III Br(Pc .3- )] .- ⋅0.875 C 6 H 4 Cl 2 ⋅0.125 C 6 H 14 (3). The salts were found to contain Pc .3- radical anions with negatively charged phthalocyanine macrocycles, as evidenced by the presence of intense bands of Pc .3- in the near-IR region and a noticeable blueshift in both the Q and Soret bands of phthalocyanine. The metal(III) atoms coordinate HFl-O - anions in 1 and 2 with short Al-O and Ga-O bond lengths of 1.749(2) and 1.836(6) Å, respectively. The C-O bonds [1.402(3) and 1.391(11) Å in 1 and 2, respectively] in the HFl-O - anions are longer than the same bond in the fluorenone ketyl (1.27-1.31 Å). Salts 1-3 show effective magnetic moments of 1.72, 1.66, and 1.79 μ B at 300 K, respectively, owing to the presence of unpaired S=1/2 spins on Pc .3- . These spins are coupled antiferromagnetically with Weiss temperatures of -22, -14, and -30 K for 1-3, respectively. Coupling can occur in the corrugated two-dimensional phthalocyanine layers of 1 and 2 with an exchange interaction of J/k B =-0.9 and -1.1 K, respectively, and in the π-stacking {[In III Br(Pc .3- )] .- } 2 dimers of 3 with an exchange interaction of J/k B =-10.8 K. The salts show intense electron paramagnetic resonance (EPR) signals attributed to Pc .3- . It was found that increasing the size of the central metal atom strongly broadened these EPR signals., (© 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.)

Crystalline anionic salts of titanyl macrocycles with acceptor substituents or an extended π-system have been obtained for the first time: (PPN + ) 2 {O[double bond, length as m-dash]Ti IV (PcCl 8 4- )} 2- (1), (PPN + ){O[double bond, length as m-dash]Ti IV (Nc˙ 3- )}˙ - ·2C 6 H 4 Cl 2 (2) and (PPN + ) 2 {O[double bond, length as m-dash]Ti IV (AceTPrzPz 4- )} 2- ·1.3C 6 H 4 Cl 2 ·0.8C 6 H 5 CN (3) where PPN + is the bis(triphenylphosphoranylidene)ammonium cation, PcCl 8 - 2,3,9,10,16,17,23,24-octachlorophthalocyanine; Nc - 2,3-naphthalocyanine, AceTPrzPz - tetra(acenaphthenopyrazino)porphyrazine. Salts 1-3 were obtained in the reduction of the parent titanyl macrocycles by fluorenone ketyl in the presence of an excess of PPNCl in o-dichlorobenzene with following precipitation of crystals with n-hexane. Reduction of macrocycles in 1-3 is accompanied by the appearance of intense NIR bands in the solid spectra at 963-1159 nm. It has been found that the extended π-system with linear annulation in {O[double bond, length as m-dash]Ti IV (Nc˙ 3- )}˙ - provides the shift of the NIR band to smaller energies (1159 nm) in comparison with those in the spectra of {O[double bond, length as m-dash]Ti IV (Pc˙ 3- )}˙ - (995-998 nm). Reduction of macrocycles leads also to the alternation of C-N imine bonds due to partial disruption of their aromaticity. The disruption is higher for the dianions in 1 and 3 in comparison with the radical anions in 2. One-dimensional π-π stacking chains and layers are formed in 1 and 3 with diamagnetic {O[double bond, length as m-dash]Ti IV (PcCl 8 4- )} 2- and {O[double bond, length as m-dash]Ti IV (AceTPrzPz 4- )} 2- dianions, respectively. Salt 2 contains nearly isolated [{O[double bond, length as m-dash]Ti IV (Nc˙ 3- )}˙ - ] 2 dimers with a strong π-π interaction between paramagnetic radical anion macrocycles. As a result, a transition from the triplet to singlet state with antiparallel ordering of spins within the dimers is observed in 2 below 200 K.

Charge transfer complexes (Cp* 2 Co + )(H 2 Pc˙ - )·0.5C 6 H 4 Cl 2 ·0.7C 6 H 5 CN·0.3C 6 H 14 (1) and (Cp* 2 Cr + )(H 2 Pc˙ - )·4C 6 H 4 Cl 2 (2) have been obtained as single crystals. Both complexes contain metal-free phthalocyanine (Pc) radical anions and decamethylmetallocenium cations. Reduction of the Pc macrocycle leads to the appearance of new bands at 1026-1030 nm in the NIR range and blue shifts of both Soret and Q-bands of H 2 Pc in the spectra of 1 and 2. The geometry of the Pc macrocycles supports the formation of H 2 Pc˙ - by the alternation of shorter and longer C-N(imine) bonds in the macrocycles in 2. Complex 1 contains pairs of H 2 Pc˙ - having effective π-π interactions with two sandwiched Cp* 2 Co + cations, whereas complex 2 contains stacks composed of alternating Cp* 2 Cr + and H 2 Pc˙ - ions. The magnetic moment of 1 is 1.64 μ B at 300 K due to the contribution of the H 2 Pc˙ - spins with the S = 1/2 state and diamagnetism of Cp* 2 Co + . This is supported by the observation of a narrow EPR signal of 1 with g = 2.0032-2.0036 characteristic of H 2 Pc˙ - . Strong antiferromagnetic coupling of spins with a Weiss temperature of -23 K is observed between H 2 Pc˙ - in 1. This coupling is probably mediated by the Cp* 2 Co + cations. The magnetic moment of 2 is 4.18 μ B at 300 K indicating the contribution of both paramagnetic H 2 Pc˙ - (S = 1/2) and Cp* 2 Cr + (S = 3/2) species. In spite of the presence of stacks of alternating ions in 2, only weak magnetic coupling is observed with a Weiss temperature of -4 K most probably due to ineffective π-π interactions between Cp* 2 Cr + and H 2 Pc˙ - . The EPR spectrum of 2 contains an asymmetric signal attributed to Cr III (g 1 = 3.9059-3.9220) and a narrow Lorentzian signal from H 2 Pc˙ - with g 2 = 1.9943-1.9961. In addition to these signals, a broad EPR signal grows in intensity below 80 K with g 4 = 2.1085-2.2438 which can be attributed to both paramagnetic Cp* 2 Cr + and H 2 Pc˙ - species having exchange interactions.

Crystalline anionic salts with copper octafluoro- and hexadecafluorophthalocyanines, (Bu 4 N + ) 2 [Cu II (F 8 Pc) 4- ] 2- ·2C 6 H 4 Cl 2 (1) and (PPN + ) 3 [CuF 16 Pc] 3 3- ·2C 6 H 5 CN (2), where PPN + is bis(triphenylphosphoranylidene)ammonium and Pc is phthalocyanine, have been obtained. The absence of noticeable absorption in the NIR range and DFT calculations for 1 indicate that both negative charges are mainly localized on the Pc ligand, and that the [Cu II (F 8 Pc) 4- ] 2- dianions are formed without reduction of Cu II . The magnetic moment of 1.60 μ B corresponds to the contribution of one S = 1/2 spin per dianion. The spin is localized on the Cu II atom, which shows an EPR signal characteristic of Cu II . Dianions are isolated in 1, providing only weak magnetic coupling of spins with a Weiss temperature of -4 K. Salt 2 contains closely packed π-π stacks built of [CuF 16 Pc] - anions of types I and II, and the interplanar distances are 3.187 and 3.275 Å. According to the DFT calculations, the [CuF 16 Pc] - anions of types I and II can have different charge distributions, with localization of an extra electron on the copper atoms to form diamagnetic [Cu I (F 16 Pc) 2- ] - monoanions or delocalization of an extra electron on the F 16 Pc ligand to form [Cu II (F 16 Pc) •3- ] •- having an S = 1/2 (Cu II ) + 1/2 (F 16 Pc •3- ) spin state. In fact, at 300 K, the magnetic moment of 2 of 3.25 μ B per formula unit is rather close to the contribution from two [Cu II (F 16 Pc) •3- ] •- (calculated μ eff is 3.46 μ B ). The Weiss temperature of -21.5 K indicates antiferromagnetic coupling of spins, which can be modeled by stronger intermolecular coupling between (F 16 Pc) •3- with J 1 /k B = -23.5 K and weaker intramolecular coupling between Cu II and (F 16 Pc) •3- with J 2 /k B = -8.1 K. This interaction is realized in the {[Cu II (F 16 Pc) •3- ] •- } 2 dimers separated by diamagnetic [Cu I (F 16 Pc) 2- ] - species. In spite of the stacking arrangement of phthalocyanine macrocycles in 2, the inhomogeneous charge distribution and nonuniform distances between the macrocycles should suppress electrical conductivity.

A spin crossover phenomena is observed in an anionic (Bu 4 N + ){Co(Ph 3 P)} 2 (μ 2 -Cl - )(μ 2 -η 2 ,η 2 -C 60 ) 2 ·2C 6 H 14 (1) complex in which two cobalt atoms bridge two fullerene molecules to form a dimer. The dimer has a triplet ground state with two weakly coupling Co 0 atoms (S = 1/2). The spin transition realized above 150 K is accompanied by a cobalt-to-fullerene charge transfer that forms a quintet excited state with a high spin Co I (S = 1) and C 60 •- (S = 1/2).

The interaction of decamethylchromocene (Cp* 2 Cr) with indigo in the presence of a Cl - source yields the coordination complex (indigo-O,O)(Cp*Cr II Cl) (1) in which one Cp* ligand at chromium is substituted by indigo. Indigo adopts an unusual cis-conformation in 1, allowing the coordination of both indigo carbonyl groups to one Cr II center. Complex 1 contains Cr II with an S = 1 spin state and indigo 0 . At the same time, calculations show that an excited ionic state is positioned close to the neutral ground state, providing the appearance of intense low-energy NIR bands in the spectrum of 1 at 820 and 1002 nm attributed to metal-to-ligand charge transfer.

Reduction of scandium nitride clusterfullerene, Sc3N@Ih-C80, by sodium fluorenone ketyl in the presence of cryptand[2,2,2] allows the crystallization of the {cryptand[2,2,2](Na(+))}2(Sc3N@Ih-C80(-))2·2.5C6H4Cl2 (1) salt. The Sc3N@Ih-C80˙(-) radical anions are dimerized to form single-bonded (Sc3N@Ih-C80(-))2 dimers.

The interaction of Sn(IV)Cl2Pc with an excess of NaBPh4 in the presence of fullerenes C60 and C70 provides complete dissolution of Sn(IV)Cl2Pc and the formation of blue solutions from which the crystals of [SnPhPc(2-)](+)(BPh4)(-)·C6H14 () or [SnPhPc˙(3-)]·C6H4Cl2 () were selectively isolated. According to the optical spectra, salt contains dianionic Pc(2-) macrocycles, whereas macrocycles are reduced to form the Pc˙(3-) radical trianions in . As a result, the phthalocyanine macrocycle is dianionic in , and the positive charge of Sn(IV) is compensated by the Ph(-), Pc(2-), and BPh4(-) anions in this compound. The formally neutral compound contains two anionic species of Ph(-) and Pc˙(3-) and the Sn(IV) ion as the counter cation. Phenyl substituents are linked to the Sn(IV) atoms by the Sn-C(Ph) bonds of 2.098(2) () and 2.105(2) Å () length. The dianionic Pc(2-) macrocycle significantly deviates from planarity in while Pc˙(3-) is planar in . Salt manifests only a weak impurity EPR signal. Compound manifests an intense EPR signal with g = 2.0046 and a linewidth of 0.5 mT at 298 K due to the presence of Pc˙(3-). Spins are weakly antiferromagnetically coupled in the π-stacking [SnPhPc˙(3-)]2 dimers of with a Weiss temperature of -3 K and the estimated magnetic exchange interaction J/kB = -0.23 K.

The reduction of fullerene C60 by zinc dust in the presence of crystal violet cations (CV(+) ) yielded a deep-blue solution, from which crystals of (CV(+) )(C60 (.-) )⋅0.5 C6 H4 Cl2 (1) were obtained by slow mixing with n-hexane. The salt contained isolated, closely packed zigzagged chains that were composed of C60 (.-) radical anions with a uniform interfullerene center-to-center distance of 9.98 Å. In spite of the close proximity of the fullerenes, they did not dimerize, owing to spatial separation by the phenyl substituents of CV(+) . The room-temperature conductivity of compound 1 was 3×10(-2)  S cm(-1) along the fullerene chains. The salt exhibited semiconducting behavior, with an activation energy of Ea =167 meV. Spins localized on C60 (.-) were antiferromagnetically coupled within the fullerene chains, with a Weiss temperature of -19 K without long-range magnetic ordering down to 1.9 K., (© 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)

The reduction of Co(II)(dppe)Cl2 with sodium fluorenone ketyl produces a red solution containing the Co(I) species. The dissolution of C60 in the obtained solution followed by the precipitation of crystals with hexane yields a salt {Co(I)(dppe)2(+)}(C60˙(-))·2C6H4Cl2 and a novel complex {Co(dppe)2Cl}(C60) (). With C70, only the crystals of {Co(dppe)2Cl}(C70)·0.5C6H4Cl2 () are formed. Complex contains zig-zag fullerene chains whereas closely packed double chains are formed from fullerenes in . According to the optical spectra and magnetic data charge transfer occurs in both and with the formation of the Co(II)(dppe)2Cl(+) cations and the C60˙(-) or C70˙(-) radical anions. In spite of the close packing in crystals, C60˙(-) or C70˙(-) retain their monomeric form at least down to 100 K. The effective magnetic moments of and of 1.98 and 2.27μB at 300 K, respectively, do not attain the value of 2.45μB expected for the system with two non-interacting S = 1/2 spins at full charge transfer to fullerenes. Most probably diamagnetic {Co(I)(dppe)2Cl}(0) and neutral fullerenes are partially preserved in the samples which can explain the weak magnetic coupling of spins and the absence of fullerene dimerization in both complexes. The EPR spectra of and show asymmetric signals approximated by several lines with g-factors ranging from 2.0009 to 2.3325. These signals originate from the exchange interaction between the paramagnetic Co(II)(dppe)2Cl(+) cations and the fullerene˙(-) radical anions.

The ability of tin atoms to form stable Sn-M bonds with transition metals was used to prepare transition metal complexes with tin(II) phthalocyanine in neutral, monoanionic, and dianionic states. These complexes were obtained via the interactions of [Sn(IV)Cl2Pc(3-)](•-) or [Sn(II)Pc(3-)](•-) radical anions with {Cp*Mo(CO)2}2, {CpFe(CO)2}2, {CpMo(CO)3}2, Fe3(CO)12, {Cp*RhCl2}2, or Ph5CpRu(CO)2Cl. The neutral coordination complexes of Cp*MoBr(CO)2[Sn(II)Pc(2-)]·0.5C6H4Cl2 (1) and CpFe(CO)2[Sn(II)Pc(2-)]·2C6H4Cl2 (2) were obtained from [Sn(IV)Cl2Pc(3-)](•-). On the other hand, the coordination of transition metals to [Sn(II)Pc(3-)](•-) yielded anionic coordination complexes preserving the spin on [Sn(II)Pc(3-)](•-). However, in the case of {cryptand[2,2,2](Na(+))}{CpFe(II)(CO)2[Sn(II)Pc(4-)]}(-)·C6H4Cl2 (4), charge transfer from CpFe(I)(CO)2 to [Sn(II)Pc(3-)](•-) took place to form the diamagnetic [Sn(II)Pc(4-)](2-) dianion and {CpFe(II)(CO)2}(+). The complexes {cryptand[2,2,2](Na(+))}{Fe(CO)4[Sn(II)Pc(3-)](•-)} (5), {cryptand[2,2,2](Na(+))}{CpMo(CO)2[Sn(II)Pc(2-)Sn(II)Pc(3-)(•-)]} (6), and {cryptand[2,2,2](Na(+))}{Cp*RhCl2[Sn(II)Pc(3-)](•-)} (7) have magnetic moments of 1.75, 2.41, and 1.75 μ(B), respectively, owing to the presence of S = 1/2 spins on [Sn(II)Pc(3-)](•-) and CpMo(I)(CO)2 (for 6). In addition, the strong antiferromagnetic coupling of spins with Weiss temperatures of -35.5 -28.6 K was realized between the CpMo(I)(CO)2 and the [Sn(II)Pc(3-)](•-) units in 6 and the π-stacking {Fe(CO)4[Sn(II)Pc(3-)](•-)}2 dimers of 5, respectively. The [Sn(II)Pc(3-)](•-) radical anions substituted the chloride anions in Ph5CpRu(CO)2Cl to form the formally neutral compound {Ph5CpRu(II)(CO)2[Sn(II)Pc(3-)]} (8) in which the negative charge and spin are preserved on [Sn(II)Pc(3-)](•-). The strong antiferromagnetic coupling of spins with a magnetic exchange interaction J/k(B) = -183 K in 8 is explained by the close packing of [Sn(II)Pc(3-)](•-) in the π-stacked {Ph5CpRu(II)(CO)2[Sn(II)Pc(3-)](•-)}2 dimers.

Crystalline anionic coordination complexes (PPN(+)){CpMo(CO)2(η(2)-C60)}(-) (), (PPN(+)){CpMo(CO)2(η(2)-C70)}(-)·0.5C6H14 () and (PPN(+)){Cp*Mo(CO)2(η(2)-C60)}(-)·C6H5CN·C6H4Cl2 () containing cyclopentadienyl (, ) and pentamethylcyclopentadienyl () molybdenum dicarbonyl η(2)-coordinated to fullerenes have been obtained by the reaction of the (PPN(+))(fullerene˙(-)) salt with the {Cp(*)Mo(CO)3(2)}2 dimers (PPN(+) is bis(triphenylphosphoranylidene)ammonium cation). The {CpMo(CO)2(η(2)-C60(70))}(-) anions contain neutral C60 and C70. The optical properties and geometry of the CpMo(CO)2 moieties in and are similar to those in (PPN(+)){CpMo(0)(CO)3}(-). The analysis of optical data for shows that η(2)-coordinated C60 molecules are more negatively charged in than in and . Complexes show weak EPR signals indicating that the major part of the samples is EPR silent and diamagnetic. Diamagnetism of the anions in is explained by the chemical bond formation between the initially paramagnetic CpMo(I)(CO)2 and (fullerene)˙(-) units. The DFT calculations for and support the diamagnetic singlet ground state for both complexes, in which the singlet-triplet energy gaps calculated at the M11/cc-pVTZ-PP/cc-pVDZ level of theory are about 1.27 and 0.95 eV, respectively. According to the calculations, C60 molecules are more negatively charged in than in and that can be explained by stronger back donation from the molybdenum moieties to fullerenes.

Coordination of two bridging cobalt atoms to fullerenes by the η(2) type in {Co(dppe)}2{μ2-η(2):η(2)-η(2):η(2)-[(C60)2]}·3C6H4Cl2 [1; dppe = 1,2-bis(diphenylphosphino)ethane] triggers fullerene dimerization with the formation of two intercage C-C bonds of 1.571(4) Å length. Coordination-induced fullerene dimerization opens a path to the design of fullerene structures bonded by both covalent C-C bonds and η(2)-coordination-bridged metal atoms.

Radical anion salts of metal-containing and metal-free phthalocyanines [MPc(3-)](·-), where M = Cu(II), Ni(II), H2, Sn(II), Pb(II), Ti(IV)O, and V(IV)O (1-10) with tetraalkylammonium cations have been obtained as single crystals by phthalocyanine reduction with sodium fluorenone ketyl. Their formation is accompanied by the Pc ligand reduction and affects the molecular structure of metal phthalocyanine radical anions as well as their optical and magnetic properties. Radical anions are characterized by the alternation of short and long C-Nimine bonds in the Pc ligand owing to the disruption of its aromaticity. Salts 1-10 show new bands at 833-1041 nm in the NIR range, whereas the Q- and Soret bands are blue-shifted by 0.13-0.25 eV (38-92 nm) and 0.04-0.07 eV (4-13 nm), respectively. Radical anions with Ni(II), Sn(II), Pb(II), and Ti(IV)O have S = 1/2 spin state, whereas [Cu(II)Pc(3-)](·-) and [V(IV)OPc(3-)](·-) containing paramagnetic Cu(II) and V(IV)O have two S = 1/2 spins per radical anion. Central metal atoms strongly affect EPR spectra of phthalocyanine radical anions. Instead of narrow EPR signals characteristic of metal-free phthalocyanine radical anions [H2Pc(3-)](·-) (linewidth of 0.08-0.24 mT), broad EPR signals are manifested (linewidth of 2-70 mT) with g-factors and linewidths that are strongly temperature-dependent. Salt 11 containing the [Na(I)Pc(2-)](-) anions as well as previously studied [Fe(I)Pc(2-)](-) and [Co(I)Pc(2-)](-) anions that are formed without reduction of the Pc ligand do not show changes in molecular structure or optical and magnetic properties characteristic of [MPc(3-)](·-) in 1-10., (© 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)

A compound containing fullerene dimers bonded through two nickel atoms, {Ni(Ph3P)}2(μ2-η(2),η(2)-C60)2·2C6H4Cl2 (1), has been obtained as single crystals. The fullerenes are neutral in 1 , showing a zero-valent state of Ni. The nickel atoms are bonded in an η(2) coordination mode with Ni-C distances of 2.001(3)-2.037(3) Å and a close approach of the fullerenes with a 9.716 Å center-to-center distance. The DFT calculations showed a diamagnetic singlet ground state for this dimer.