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Here we report the synthesis of novel fullerene derivatives with attached aliphatic residues based on the previously unknown reactions of chlorofullerene C 60 Cl 6 with CH-acids and silyl enol ether.

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.

In this article, the specific features of competitive ionic and molecular transport in nanocomposite systems based on network membranes synthesized by radical polymerization of polyethylene glycol diacrylate in the presence of LiBF 4 , 1-ethyl-3-methylimidazolium tetrafluoroborate, ethylene carbonate (EC), and TiO 2 nanopowder (d~21 nm) were studied for 1 H, 7 Li, 11 B, 13 C, and 19 F nuclei using NMR. The membranes obtained were studied through electrochemical impedance, IR-Fourier spectroscopy, DSC, and TGA. The ionic conductivity of the membranes was up to 4.8 m Scm -1 at room temperature. The operating temperature range was from -40 to 100 °C. Two types of molecular and ionic transport (fast and slow) have been detected by pulsed field gradient NMR. From quantum chemical modeling, it follows that the difficulty of lithium transport is due to the strong chemisorption of BF 4 - anions with counterions on the surface of TiO 2 nanoparticles. The theoretical conclusion about the need to increase the proportion of EC in order to reduce the influence of this effect was confirmed by an experimental study of a system with 4 moles of EC. It has been shown that this approach leads to an increase in lithium conductivity in an ionic liquid medium, which is important for the development of thermostable nanocomposite electrolytes for Li//LiFePO 4 batteries with a base of lithium salts and aprotonic imidasolium ionic liquid.

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 growing demand for cheap, safe, recyclable, and environmentally friendly batteries highlights the importance of the development of organic electrode materials. Here, we present a novel redox-active polymer comprising a polyaniline-type conjugated backbone and quinizarin and anthraquinone units. The synthesized polymer was explored as a cathode material for batteries, and it delivered promising performance characteristics in both lithium and potassium cells. Excellent lithiation efficiency enabled high discharge capacity values of >400 mA g -1 in combination with good stability upon charge-discharge cycling. Similarly, the potassium cells with the polymer-based cathodes demonstrated a high discharge capacity of >200 mAh g -1 at 50 mA g -1 and impressive stability: no capacity deterioration was observed for over 3000 cycles at 11 A g -1 , which was among the best results reported for K ion battery cathodes to date. The synthetic availability and low projected cost of the designed material paves a way to its practical implementation in scalable and inexpensive organic batteries, which are emerging as a sustainable energy storage technology.

Elementary processes of electro mass transfer in the nanocomposite polymer electrolyte system by pulse field gradient, spin echo NMR spectroscopy and the high-resolution NMR method together with electrochemical impedance spectroscopy are examined. The new nanocomposite polymer gel electrolytes consisted of polyethylene glycol diacrylate (PEGDA), salt LiBF 4 and 1-ethyl-3-methylimidazolium tetrafluoroborate (EMIBF 4 ) and SiO 2 nanoparticles. Kinetics of the PEGDA matrix formation was studied by isothermal calorimetry. The flexible polymer-ionic liquid films were studied by IRFT spectroscopy, differential scanning calorimetry and temperature gravimetric analysis. The total conductivity in these systems was about 10 -4 S cm -1 (-40 °C), 10 -3 S cm -1 (25 °C) and 10 -2 S cm -1 (100 °C). The method of quantum-chemical modeling of the interaction of SiO 2 nanoparticles with ions showed the advantage of the mixed adsorption process, in which a negatively charged surface layer is formed from Li + BF 4 - ions on silicon dioxide particles and then from ions of the ionic liquid EMI + BF 4 - . These electrolytes are promising for use both in lithium power sources and in supercapacitors. The paper shows preliminary tests of a lithium cell with an organic electrode based on a pentaazapentacene derivative for 110 charge-discharge cycles.

We report a novel reaction of the recently discovered family of fullerene derivatives C 1 -C 60 Ar 5 Th' with thiophene derivatives Th''H yielding a previously unknown family of C 1 -C 60 Ar 5 Th'Th''H compounds with three different types of functional aromatic addends attached to the carbon cage. The discovered reaction paves a way to the synthesis of novel C 60 fullerene derivatives with promising antioxidant and antiviral properties.

The influenza virus genome features a very high mutation rate leading to the rapid selection of drug-resistant strains. Due to the emergence of drug-resistant strains, there is a need for the further development of new potent antivirals against influenza with a broad activity spectrum. Thus, the search for a novel, effective broad-spectrum antiviral agent is a top priority of medical science and healthcare systems. In this paper, derivatives based on fullerenes with broad virus inhibiting activities in vitro against a panel of influenza viruses were described. The antiviral properties of water-soluble fullerene derivatives were studied. It was demonstrated that the library of compounds based on fullerenes has cytoprotective activity. Maximum virus-inhibiting activity and minimum toxicity were found with compound 2 , containing residues of salts of 2-amino-3-cyclopropylpropanoic acid (CC 50 > 300 µg/mL, IC 50 = 4.73 µg/mL, SI = 64). This study represents the initial stage in a study of fullerenes as anti-influenza drugs. The results of the study lead us conclude that five leading compounds ( 1 - 5 ) have pharmacological prospects.

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.

The effect of the composition of liquid electrolytes in the bulk and at the interface with the LiFePO 4 cathode on the operation of a solid-state lithium battery with a nanocomposite polymer gel electrolyte based on polyethylene glycol diacrylate and SiO 2 was studied. The self-diffusion coefficients on the 7Li, 1H, and 19F nuclei in electrolytes based on LiBF 4 and LiTFSI salts in solvents (gamma-butyrolactone, dioxolane, dimethoxyethane) were measured by nuclear magnetic resonance (NMR) with a magnetic field gradient. Four compositions of the complex electrolyte system were studied by high-resolution NMR. The experimentally obtained 1 H chemical shifts are compared with those theoretically calculated by quantum chemical modeling. This made it possible to suggest the solvate shell compositions that facilitate the rapid transfer of the Li + cation at the nanocomposite electrolyte/LiFePO 4 interface and ensure the stable operation of a solid-state lithium battery.

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).

Photo-switchable organic field-effect transistors (OFETs) represent an important platform for designing memory devices for a diverse array of products including security (brand-protection, copy-protection, keyless entry, etc.), credit cards, tickets, and multiple wearable organic electronics applications. Herein, we present a new concept by introducing self-assembled monolayers of donor-acceptor porphyrin-fullerene dyads as light-responsive triggers modulating the electrical characteristics of OFETs and thus pave the way to the development of advanced nonvolatile optical memory. The devices demonstrated wide memory windows, high programming speeds, and long retention times. Furthermore, we show a remarkable effect of the orientation of the fullerene-polymer dyads at the dielectric/semiconductor interface on the device behavior. In particular, the dyads anchored to the dielectric by the porphyrin part induced a reversible photoelectrical switching of OFETs, which is characteristic of flash memory elements. On the contrary, the devices utilizing the dyad anchored by the fullerene moiety demonstrated irreversible switching, thus operating as read-only memory (ROM). A mechanism explaining this behavior is proposed using theoretical DFT calculations. The results suggest the possibility of revisiting hundreds of known donor-acceptor dyads designed previously for artificial photosynthesis or other purposes as versatile optical triggers in advanced OFET-based multibit memory devices for emerging electronic applications.

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.)

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.

Here we report a reaction of the fullerene derivatives C 60 Ar 5 Cl, which enables the substitution of Cl with thiophene residues and the formation of the novel family of C 1 -symmetrical C 60 fullerene derivatives with six functional addends C 60 Ar 5 Th. The discovered reaction provided a straightforward approach to the synthesis of previously inaccessible multifunctional water-soluble fullerene derivatives, including the compounds with antiviral activity against human immunodeficiency and influenza viruses.

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.

Regardless of the impressive photovoltaic performances demonstrated for lead halide perovskite solar cells, their practical implementation is severely impeded by the low device stability. Complex lead halides are sensitive to both light and heat, which are unavoidable under realistic solar cell operational conditions. Suppressing these intrinsic degradation pathways requires a thorough understanding of their mechanistic aspects. Herein, we explored the temperature effects in the light-induced decomposition of MAPbI 3 and PbI 2 thin films under anoxic conditions. The analysis of the aging kinetics revealed that MAPbI 3 photolysis and PbI 2 photolysis have quite high effective activation energies of ∼85 and ∼106 kJ mol -1 , respectively, so decreasing the temperature from 55 to 30 °C can extend the perovskite lifetime by factors of >10-100. These findings suggest that controlling the temperature of the perovskite solar panels might allow the long operational lifetimes (>20 years) required for the practical implementation of this promising technology.

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.

Here we report the Friedel-Crafts arylation of chlorofullerenes C60Cl6 and C70Cl8 with thiophene-based methyl esters. While C60Cl6 formed expected Cs-C60R5Cl products, C70Cl8 demonstrated a tendency for both substitution of chlorine atoms and addition of an extra thiophene unit, thus forming Cs-C70R8 and C1-C70R9H compounds. The synthesized water-soluble C60 and C70 fullerene derivatives with thiophene-based addends demonstrated high activity against a broad range of viruses, including human immunodeficiency virus, influenza virus, cytomegalovirus, and herpes simplex virus. The record activity of C70 fullerene derivatives against herpes simplex virus together with low toxicity in mice makes them promising candidates for the development of novel non-nucleoside antiherpetic drugs.

Here we report a straightforward method for the synthesis of a water-soluble C60 fullerene derivative decorated with five residues of phosphonic acid. Self-assembly of the synthesized compound in aqueous solution leads to the formation of nanostructures with unprecedented myogenic and antiviral activity.

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.)

We report unprecedented Friedel-Crafts arylation of chlorofullerenes C60Cl6 and C70Cl8 with unprotected carboxylic acids as an efficient single-step synthesis of the inherently stable water-soluble fullerene derivatives. Using this method, a series of previously unaccessible compounds was obtained without chromatographic purification in almost quantitative yields. Promising anti-HIV activity comparable to characteristics of commercial drugs was demonstrated for some of these compounds.

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.

We report an "inversed" Arbuzov reaction of the fullerene derivatives C 60 Ar 5 Cl with trialkyl phosphites P(OR) 3 producing alkylated fullerene derivatives C 60 Ar 5 R (R = Me, Et, iPr, nBu) with almost quantitative yields. This reaction provides a convenient synthetic route for the preparation of a large variety of functionalized fullerene derivatives with tailored properties, e.g. water-soluble compounds demonstrating promising antiviral activities against HCMV, HSV1, HIV and several influenza virus strains.

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.

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.

We report an unusual thermal condensation of readily available tetracyanocyclopropanes to tetracyanosubstituted triazaphenalenes, which revealed interesting optoelectronic properties such as strongly pronounced solvatochromism and bright photoluminescence. Optical memory elements and organic light emitting diodes with a deep red electroluminescence were designed using triazaphenalenes, thus highlighting the potential of these compounds as materials for electronic applications.

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.

A series of novel cluster compounds comprising molybdenum in a low valence state was synthesized by means of a disproportionation of the dimeric compound [Mo +4 2 Cl 4 (OCH 3 ) 4 (CH 3 OH) 2 ] (1). The reaction of 1 with CH 3 OH leads to the disproportionation of Mo +4 yielding an unusual mixed-valence cluster [Mo +3.5 4 Cl 4 O 2 (OCH 3 ) 6 (CH 3 OH) 4 ] (2). By exploring this synthetic approach further, tri-{[Mo 3 Cl 3 (OCH 3 ) 7 (CH 3 OH) 3 ] (3)}, tetra-{[Mo 4 Cl 4 (OCH 3 ) 10 (CH 3 OH) 2 ] (4), [Mo 4 Cl 3 O(OCH 3 ) 9 (CH 3 OH) 3 ] (5), [Mo 4 Cl 2 (OCH 3 ) 12 (CH 3 OH) 2 ] (6)}, and hexanuclear {[Mo 6 Cl 4 O 6 (OCH 3 ) 10 (CH 3 OH) 2 ] (7)} molybdenum alkoxides were synthesized by the reaction of 1 with methanol and stoichiometric amounts of magnesium methoxide, thus providing a general facile access to the polynuclear methoxide complexes of a low-valence molybdenum. Due to the feasibility to adopt multiple oxidation states in a reversible manner and the documented competence of molybdenum alkoxide compounds to catalyze the reduction of inert molecules, including N 2 , the synthesized compounds were expected to function as catalysts of small molecule substrates reduction/hydrogenation. Accordingly, the reduction of acetylene (C 2 H 2 ) to an ethylene (C 2 H 4 ) and ethane (C 2 H 6 ) mixture, in methanol (with water additives) serving as a reaction medium and a proton donor, and using sodium or europium amalgams as reducing agents, was performed in the presence of 2. Preliminary kinetic studies evidently point to a catalytic function of molybdenum species derived from 2, thus establishing the observed reactivity as a rare example of non-precious metal-catalyzed acetylene hydrogenation, providing, in addition, a convenient model for further mechanistic studies.

Unprecedented complexes of the composition Ln3I5(S2N2)(S2)(THF)10 were obtained in the reactions of neodymium and dysprosium iodide-nitrides with sulfur. The inorganic core of the molecules contains the cyclic fragments Ln(μ-S2)Ln, LnSNSN and LnSN. Ten of the fourteen atoms of the core are coplanar, the remaining four S2 and I2 atoms lie in the other two orthogonal planes. The dysprosium complex upon excitation with UV light exhibits the metal-centered luminescence characteristic of the Dy(3+) ion. Geometric parameters of the molecules, computational data, electron spectroscopy and fluorescence suggest the existence of some conjugation in the mentioned heterocycles.

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.

Supported gold nanoparticles are promising catalysts for production of H2O2 from O2 and H2. Size, structure, and palladium doping effects play the key role in activity and selectivity of a gold catalyst. We performed a study of the influence of Au20 and Au19Pd structure features on the main steps of H2O2 formation on the atomic level, using the DFT/PBE approach with relativistic all electron basis set. The top, edge, and facet atoms of the tetrahedral Au20 cluster as well as a palladium atom of Au19Pd located on the top, edge, and facet of a tetrahedron have been considered as active sites of steps involved in H2O2 synthesis. The thermodynamic and kinetic data including Gibbs free energies and the activation Gibbs free energies were calculated for the steps determining the formation of H2O2 (H(s) + OOH(s) = H2O(2(s)), H2O(2(s)) = H2O(2(g))) and for one step decreasing the selectivity (H2O(2(s)) = OH(s) + OH(s)). Gold tends to have low activity and high selectivity in H2O2 synthesis regardless of the structure of active site. Low coordinated palladium atoms promote H2O2 formation as well as its dissociation. Pd on a facet of a cluster facilitates H2O2 production with high activity and selectivity.

The catalytic mechanism of molybdenum containing CO dehydrogenase has been studied using hybrid DFT methods with quite large chemical models. The recent high-resolution X-ray structure, showing the surprising presence of copper linked to molybdenum, was used as a starting point. A pathway was initially found with a low barrier for C-O bond formation and CO2 release. However, this pathway did not include the formation of any S-CO2 species, which had been suggested by experiments with an n-butylisocyanide inhibitor. When these SCO2 structures were studied they were found to lead to deep minima, making CO2 release much more difficult. A large effort was spent, including investigations of other spin states, varying the number of protons and electrons, adding water, etc., until a plausible pathway for S-C bond cleavage was found. In this pathway a water molecule is inserted in between molybdenum and the SCO2 group. Full catalytic cycles, including electron and proton transfers, are constructed both with and without S-C bond formation. When these pathways are extended to two full catalytic cycles it can be understood why the formation of the S-C bond actually makes catalysis faster, even though the individual step of CO2 release becomes much more difficult. These results agree well with experimental findings., ((c) 2005 Wiley Periodicals, Inc.)

We report a density functional theory study on the heme metabolism in heme oxygenase using iron-hydroperoxo and -oxo models. The activation energies for heme oxidation at the alpha-carbon by the iron-hydroperoxo and -oxo species are calculated to be 42.9 and 39.9 kcal/mol, respectively. These high activation barriers lead us to reconsider the catalytic mechanism of heme oxygenase