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The reactions of imino phenols 3,5-But2-2-HOC6H2CH=NX (X = 8-C9H6N, 2-MeO-5-MeC6H3 and 2-PhOC6H4) with Sc(CH2SiMe3)3(THF)2 in toluene proceed with silane elimination and reductive alkylation of the C N group affording dimeric base-free monoalkyl scandium complexes. X-ray analysis of the two complexes revealed their dimeric structures due to μ-bridging amidophenolato dianions. The complexes catalyze hydrophosphination of styrene, phenylacetylene and tolane with Ph2PH as well as dehydrogenative coupling of anisole with hydrosilanes.

Transmission diffraction electron microscopy is used to study the evolution of a dislocation structure during active plastic deformation in copper–aluminum alloys in the 0–14 at % Al range of concentrations. Types of dislocation substructures are determined from micrographs, depending on the concentration of the alloying element. The parameters of the defect structure are measured and their relationship to stacking fault energy is established.

International audience

The reaction of zinc chloride with 2-benzylideneamino-5-methylphenol (LH), a bidentate Schiff base, in 1 : 1 molar ratio in the presence of triethylamine gives the ionic complex [Et3NH]+[LZnCl2]– (I). The reaction between the zinc salt (chloride or acetate) and LH in 1 : 2 ratio results in complete displacement of the zinc salt anions to give bis-o-iminophenolate ZnL2 (II), which exists in the crystalline state as the (ZnL2)2 dimer formed via μ-bridging oxygen atoms of two out of the four o-iminophenolate ligands. The molecular structure of ligand LH and complexes I and (II·CDCl3)2 was established by X-ray diffraction (CIF files CCDC nos. 2052647 (LH), 2052645 (I), 2052646 (II·CDCl3)2).

Abstract The electron density distributions obtained by the quantum-chemical (density functional theory) calculations and molecular invariom model in the trimeric ytterbium complex with the hexafluoroisopropoxide ligands {$${\text{Yb}}_{{\text{2}}}^{{{\text{II}}}}$$(μ2-OR)3(μ3-OR)2YbIII(OR)2(THF)(Et2O)} (I) (where R is CH(CF3)2, and THF is tetrahydrofuran) are compared. The main topological characteristics of the electron density at the critical points (3, –1) corresponding to the interactions of the ytterbium atoms in the coordination sphere obtained using two studied approaches demonstrate excellent agreement. The maximum divergence between the density functional calculations and molecular invariom model is observed for the intramolecular interactions involving the fluorine atoms (F···F, F···H, and F···O) in the structure of complex I. Geometry optimization leads to a higher number of these interactions in the complex. The energy corresponding to these interactions also increases. However, the main topological characteristics for the F···X interactions (X = F, H, O), which can be localized in the framework of both methods, remain within the transferability index range. An analysis of the deformation electron density shows that the Fδ–···Fδ– interactions are determined by the correspondence of the region of electron density concentration on one of the fluorine atoms to the region of electron density depletion on the second fluorine atom regardless of the method of measuring the electron density distribution.

This study reports four SMMs based on silanolate or stannanolate ligands cis-[Dy(OSiPh3)2(THF)4][BPh4]·THF·C6H6 (1), cis-[Dy(OSnPh3)2(THF)4][BPh4]·THF·C6H6·C6H14 (2), fac-[Dy(OSiPh3)3(THF)3]·THF (3) and fac-[Dy(OSiPh3)3(bipy)(THF)]·THF (4).

We report the synthesis and structures of three luminescent dysprosium(iii) complexes based on fluorinated alkoxide ligands of formulas [Dy(L1)2(THF)4][BPh4]·0.5THF (1), [Dy(L2)2(THF)5][BPh4]·2.5THF (2) and [Dy(L3)2(THF)5][BPh4]·2THF (3) (L1 = (CF3)3CO-, L2 = C6F5C6F4O-, L3 = C6F5C(CH3)O-). Despite the different dysprosium ion geometries (octahedral vs. distorted pentagonal bipyramidal), these systems exhibit a single-molecule magnet (SMM) behavior, but with distinct relaxation dynamics. Moreover, a typical dysprosium-based luminescence is observed for the three complexes, which make them bifunctional magneto-luminescent SMMs. Remarkably, complex 3 exhibits a high anisotropy barrier of 1469 cm-1 and a blocking temperature of 22 K, making it one of the most performant alkoxide-based SMMs with the highest blocking temperature for a luminescent SMM.

The outcome of salt metathesis reactions between the equimolar amounts of LnCl3 and dimeric potassium diphenylmethanide {[2,2′-(4-MeC6H3NMe2)2CH]K(THF)}2 depends on the rare-earth metal ion. In the case of ScIII and YIII, the reactions afford chlorido-bis(diphenylmethanido) complexes {[2,2′-(4-MeC6H3NMe2)2CH]2LnIII(μ-Cl)}2, in which the diphenylmethanido ligands perform bidentate κ2-CN coordination according to the X-ray data. For YbIII and SmIII, these reactions result in the spontaneous reduction of LnIII to LnII and the formation of known bis(diphenylmethanido) complexes [2,2′-(4-MeC6H3NMe2)2CH]2LnII and the product of oxidative coupling of diphenylmethanido anions.

Two synthetic approaches were developed for the preparation of 3,6-di-tert-butyl-2-hydroxy-4-pyridinylphenolate (LH), a new zwitter-ionic redox-active diolate type ligand. Two heteroligand five-coordinate tin(IV) derivatives were prepared with this ligand: 3,6-di-tert-butyl-2-oxy-4-pyridinylphenolato(triphenyl)tin(IV) (I) and 3,6-di-tert-butyl-2-oxy-4-pyridinylphenolato(diphenyl)chlorotin(IV) (II). The molecular structures of the ligand LH ∙ 0.5Py and complex I ∙ CH3CN were determined by X-ray diffraction (CIF files CCDC nos. 1974166 (LH), 1974165 (I)). It was shown that the ligand LH and the tin(IV) compound exhibit solvatochromism, which consists in a considerable blue shift with increasing solvent polarity.

New paramagnetic tin(IV) derivatives containing the radical-anion of 2,4,6,8-tetra-tert-butylphenoxazin-1-one redox-active ligand (phenox-imQ) are synthesized and studied by EPR spectroscopy. Complexes I–V are paramagnetic in the crystalline state and in solution. The geometry of the obtained paramagnetic species and spin density distribution in them are studied by the Density functional theory. Diamagnetic complex VI is synthesized from the phenox-imQ dianion, and its one-electron oxidation is studied. The molecular structure of complex VI · ТHF is determined by X-ray diffraction analysis (CIF file CCDC no. 2000962 (VI · ТHF)).

The reaction of benzophenone hydrazone with chlorodiphenylphosphine in the presence of triethylamine affords the monophosphino derivative Ph2C=N-N(H)PPh2(1). The lithiation of 1 with one equivalent of MeLi produces the stable salt Ph2C=N-N(Li)PPh2, and the addition of the second equivalent of MeLi results in the lithiation of the aromatic ring of the Ph2C group followed by the cyclization to lithium-substituted diazaphosphinine. The treatment of the latter with chlorotrimethylsilane furnishes 1,4-diphenyl-2-trimethylsilyl-1,2-dihydrobenzo-[d][1,2,3]diazaphosphinine. Phosphinohydrazone 1 gives 2: 1 complexes with cobalt and nickel bromides, which were characterized by X-ray diffraction. The migratory insertion of the Ph2P group into the N-N bond was not observed in phosphinohydrazone derivatives, as opposed to phosphinohydrazides M-NR-NR-PPh2 (M is metal).

The exchange reaction of anhydrous YbCl3 with [1,3-C6H4{NC(Ph)N(SiMe3)}2Li2(THF)2]2 (I) (4 : 3 molar ratio, THF) gave ansa-bis(amidinate) ytterbium complex [1,3-C6H4{NC(Ph)N(SiMe3)}2]3Yb2 (II) in which three bis(amidinate) ligands form µ-bridges between two Yb3+ ions. An X-ray diffraction study (CIF file CCDC no. 1964848) showed that the dimeric structure of II is formed upon simultaneous coordination of κ2-N,N-chelating moieties of three ligands to two ytterbium atoms.

The exchange reactions of equimolar amounts of potassium penta(benzyl)cyclopentadienide CpBn5K (CpBn5 = C5(CH2Ph)5) and SmI2(THF)2 or YCl3 afforded the corresponding half-sandwich derivatives [CpBn5Sm(DME)(μ-I)]2 (1) and [CpBn5YCl2(THF)]2[KCl(THF)2] (2). According to the X-ray diffraction data, the metal ions in complexes 1 and 2 are coordinated by CpBn5 ligands in a η5-fashion. The difference is that there is a short contact between the SmII cation and one benzyl group of the cyclopentadienyl ligand in structure 1, whereas such interaction is absent in structure 2.

The addition of different substituted o-benzoquinones and o-iminobenzoquinones to tin(II) bis(o-iminophenolates) of the types (Fc-IP)2SnII and (Fc-4,6-IP)2SnII (where Fc-IP is anion 2-(ferrocenylme...

New bis-p-iminobenzoquinone ligands, in which two hydroxy-p-iminobenzoquinone moieties are bridged by various functionalized linkers, were synthesized by 1,4-addition of aromatic diamines to 3,6-di-tert-butyl-o-benzoquinone. The exchange reaction between potassium salts of new ligands and ethylmercury(ii) chloride produces the corresponding mono- and binuclear metal complexes. In these complexes, the mercury atoms exhibit T-shaped trigonal geometry characteristic of three-coordinate mercury(ii) derivatives. The structures of the new ligands and the mercury complexes with these ligands were determined by IR, UV, and NMR spectroscopy and X-ray diffraction.

The reaction of the amidinatehydride complex of divalent ytterbium [(Amd)YbII(μ2-H)]2 (Amd is {tert-BuC(NC6H3-iso-Pr2-2,6)2}) with BPh3 proceeds with the cleavage of the B−C bonds and affords the Yb(II)[(Amd)YbII(μ2-H3BPh)]2 complex containing the phenyltrihydroborate anion [PhBH3]−. The X-ray diffraction analysis (СIF file CCDC no. 1902290) shows that the [PhBH3]− anions in the complex are bridging. The “nonclassical” κ1-amido-η6-arene coordination mode to the Yb2+ ion is retained for the amidinate ligand.

A series of heterospin bis-o-semiquinone cobalt, nickel, and copper complexes (4-TEMPO-oxy-3,6-di-tert-butyl-o-benzoquinone derivatives) is synthesized: (DMSO)Cu(4-TEMPO-O-3,6-DBSQ)2 (I), (THF)2Ni(4-TEMPO-O-3,6-DBSQ)2 (II), (Py)2Ni(4-TEMPO-O-3,6-DBSQ)2 (III), and (Py)2Ni(4-TEMPO-O-3,6-DBSQ)2 (IV) (4-TEMPO-O-3,6-DBQ is 4-(3,6-di-tert-butyl-1,2-dioxocyclohexa-3,5-dien-4-yloxy)-2,2,6,6-tetramethylpiperidine-1-oxyl 4-oxy-2,2',6,6'-tetramethylpiperidine-1-oxyl). All complexes are characterized by elemental analysis, IR spectroscopy, magnetochemistry, and EPR. The structure of complex I is determined by X-ray diffraction analysis (CIF file CCDC no. 1882878). The coordination polyhedron of the copper atom in the molecular structure of the Cu(II) bis-o-semiquinone complex with dimethyl sulfoxide (DMSO) is a distorted tetragonal pyramid, whose equatorial plane contains the o-semiquinone ligands, and the DMSO molecule occupies the apical position. The magnetic properties of complexes I–IV are consistent with their compositions and structures. The magnetic behavior of copper complex I and nickel complexes II and III is determined by the balance of two contributions: metal–ligand ferromagnetic exchange interaction and ligand–ligand antiferromagnetic interaction. The temperature dependence of the magnetic moment of cobalt complex IV shows the redox isomeric transformation conjugated with the spin transition, which is characteristic of complexes of this type. No participation of nitroxyl radical centers is observed in intermolecular coordination.

New stannylene AdAPSn (I) based on 4,6-di-tert-butyl-N-adamantyl-o-aminophenol is synthesized and structurally characterized. Stannylene I in the crystalline state forms infinite chains due to intermolecular donor–acceptor Sn–N and metallophilic Sn···Sn interactions. The reactivities of compound I and earlier synthesized t-BuAPSn (II) are studied using their redox and acid–base reactions. Stannylenes I and II are inserted at the S–S bond of tetramethylthiuram disulfide to form the corresponding tin(IV) dithiocarbamate complexes. The reactions with soft one-electron oxidants involve the redox-active o-amidophenolate ligand and generate labile paramagnetic stannylenes studied by EPR spectroscopy. The presence of a lone electron pair at the low-valence tin atom is a reason for its basic properties, which is demonstrated for the reaction of compound I with nanocarbonyl iron. The structures of selected synthesized compounds are determined by X-ray diffraction analysis (СIF files CCDC nos. 1905419–1905421).

Two synthetic approaches were used for the synthesis of 3,6-di-tert-butylcatecholate derivatives of titanium(iv). These approaches are based on the exchange reaction between sodium catecholate and titanium(iv) chloride and the reaction of 3,6-di-tert-butylpyrocatechol with titanium tetrabutoxide. Depending on the reaction conditions, the former method allows the synthesis of the titanium monocatecholate complex 3,6-CatTiCl2(THF)2 (3,6-Cat is doubly deprotonated 3,6-di-tert-butylpyrocatechol) or bimetallic sodium titanium catecholate derivatives. Using the latter method, it is possible to synthesize six-coordinate titanium(iv) bis-cate-cholate complexes in high yields after the introduction of neutral bidentate donor ligands (TMEDA, DME, 2,2′-bipyridyl) to the reaction mixture.

Cobalt(iii) complexes with different 4,6-di-tert-butyl-N-(aryl)-o-iminobenzosemiquinone ligands were synthesized. Four-, five-, or six-coordinate cobalt(iii) derivatives can be prepared using various starting metal compounds (CoCl2•6H2O, (acac)2Co•2H2O) and varying substituents in the N-aryl moiety of the organic ligand. The structures of five synthesized compounds were determined by X-ray diffraction. The electronic and spin states of the five-coordinate cobalt(iii) complexes were studied in detail by DFT quantum chemical calculations.

On treatment of the yttrium bis(alkyl) complex [ArNC(=CH2)C(Me)=NAr]Y(CH2SiMe3)2(THF) (I, Ar = C6H3-iso-Pr2-2.6) containing an amide-imine ligand, with molecular hydrogen, hydrogenation of the C=N and C=C bonds takes place along with hydrogenolysis of Y−C bonds. The reaction is also accompanied by redistribution of nitrogen ligands and results in the formation of the yttrium complexes [ArNCH(Me)CH(Me)NAr]Y[ArN(=CH2)CH(Me)N(H)Ar](THF) (IIMeMe) and [ArNCH(Me)-C(=CH2)NAr]Y[ArN(=CH2)CH(Me)N(H)Ar](THF) containing, the monoanionic ene-amide-amine moiety [ArNC(=CH2)CH(Me)N(H)Ar]−, together with the dianionic diamide ligands [ArNCH(Me)CH(Me)NAr]2− or [ArNCH(Me)C(=CH2)NAr]2− (CIF file CCDC no. 1873206).

Six-coordinate metal complexes containing tridentate Schiff bases with an ONN-chelating moiety were prepared by template synthesis on tin tetrachloride using various aminophenols and α-carbonyl-substituted pyridines. The structures of five compounds were studied by X-ray diffraction (CIF files CCDC nos. 849152–1849156). The UV/Vis spectra of the obtained series of compounds were found to be highly sensitive to the nature of substituents in the moieties of organic ligand.

The deprotonation of amidine 2-[Ph2P(O)]C6H4NHC(But)=N(2,6-Me2C6H3) (1) with BunLi affords lithium amidinate {2-[Ph2P(O)]C6H4NLiC(But)=N(2,6-Me2C6H3)}2 (2) having a dimeric structure, as demonstrated by X-ray diffraction. New amidinate dihalide complexes {2-[Ph2P(O)]C6H4NC(But)N(2,6-Me2C6H3)}NdHal2(THF)2 (Hal = I (3), Cl (4)) were synthesized by exchange reactions of lithium and potassium amidinates with anhydrous neodymium halides NdHal3(THF)n (Hal = I, n = 3.5; Cl, n = 0). The X-ray diffraction studies showed that the new compounds are monomeric and the amidinate ligand is tridentate. Chloride complex 4 involved in the three- and four-component catalyst systems 4–AlR3–[Ph3C] [B(C6F5)4] (1: 10: 1; AlR3 = AlBui 3, AlMe3), 4–AlR3–PriOH (1: 10: 10; AlR3 = AlBui3, AlMe3), and 4–AlR3–[Ph3C][B(C6F5)4]–PriOH (1: 10: 1: 10; AlR3 = AlBui3, AlMe3) exhibits activity in stereospecific isoprene polymerization and allows the preparation of high-molecular-weight polyisoprene samples with exceptionally high cis-1,4-unit content (up to 99.4%).

International audience; We report the synthesis, magnetic and photoluminescence investigations of two bifunctional dysprosium complexes based on tridentate Schiff base ligands. Magnetic investigations reveal a genuine Single-Molecule Magnet (SMM) behavior with out-of-phase signals up to 60 K, and the tunable emission arising from the Schiff base ligands.

International audience; We report the synthesis, structure and magnetic properties' investigations of a series of new dysprosium heteroleptic mono-and dinuclear complexes based on the association of chloride and different diazabutadiene (DAD 2R = [2,6-iPr2C6H3N-CRCR-NC6H3iPr2-2,6]; R = H, Me) ligands showing different redox states. While using dianionic DAD 2R ligands affords the formation of dichloro-bridged dinuclear complexes [Dy2(DAD 2R)(-Cl)2(THF)2] (R = H (1), Me (2)), two different mononuclear complexes of general formula [DyCl2(DAD 2R)(THF)2] (R = H (3), Me (4)) could be obtained with either a radical monoanionic and a monoanionic DAD 2R state, respectively. Remarkably, all the complexes exhibit a slow relaxation of their magnetization where the relaxation dynamics depends on both, the nuclearity of the system and the DAD 2R redox state.

International audience; We report here the synthesis, structure, magnetic and photoluminescence properties of three new bifunctional Schiff-base complexes [Dy(L1)2(py)2][B(Ph)4]•py (1), [Dy(L1)2Cl(DME)]•0.5DME (2) and [Dy(L2)2Cl]•2.5(C7H8) (3) (HL1 = Phenol, 2,4-bis(1,1dimethylethyl)-6-[[(2-methoxy-5-methylphenyl)imino]methyl]; HL2 = Phenol, 2,4-bis(1,1-dimethylethyl)-6-[[(2-methoxyphenyl)imino] methyl]). The coordination environment of the Dy 3+ ion and the direction of the anisotropic axis may be controlled by the combination of the substituent groups of the Schiff bases, the nature of the counter-ions (Cl  vs. BPh4 ) and the coordinative solvent molecules. A zero-field slow relaxation of the magnetization is evidenced for all complexes but strong differences in the relaxation dynamics are observed depending on the Dy 3+ site geometry. In this sense, complex 1 exhibits an anisotropic barrier of 472 cm 1 , which may be favourably compared to other related examples due to the shortening of the Dy-O bond in the axial direction. Besides, the three complexes exhibit a ligand-based luminescence making them as bifunctional magneto-luminescent systems.

The reaction of cyclohexane-annulated 3 a,6a-diaza-1,4-diphosphapentalene (DDP) with di-tert-butyl acetylenedicarboxylate (DBAD) affords the 1,3-dipolar cycloaddition product of the acetylene moiety to the phosphorus and sp2-carbon atoms of DDP in 90% yield. No individual products were isolated in the reaction of DDP with dimethyl acetylenedicarboxylate (DMAD). In the three-component DDP–DMAD–carbazole system (1: 2: 1), a product was generated in 73% yield via successive reactions, including the 1(P),3(C)-dipolar cycloaddition of DMAD to DDP, the addition of the second equivalent of DMAD to the three-coordinate phosphorus atom of the intermediate, and the NH addition of carbazole at the unsaturated C=C bond of the second DMAD moiety. The structures of the reaction products were established by X-ray diffraction.

In an attempt to get more insight into the way of formation of recently obtained unusual iodide-sulfide-nitride clusters Ln 3 I 5 (S 2 )(S 2 N 2 )(THF) 10 (Ln = Nd ( 1 ), Dy ( 2 )) and modify this synthesis reactions of dysprosium iodide-nitride with sulfur were carried out in various conditions. It was found that the reaction of as prepared dysprosium iodide-nitride [(DyI 2 ) 3 N] x with sulfur in THF yields ionic complex {[DyI 2 (THF) 5 ] + [DyI 2 S 5 (THF) 2 ] − } ( 3 ) anionic part of which contains six-membered cycle DyS 5 . The same reaction in iso -propylamine medium affords ionic iodide-sulfide{[( i PrNH 2 ) 4 Dy(μ- η 2 :η 2 - S 2 )] 2 } 2+ [I − ] 2 ( 4 ) containing bipyramide core formed by two apical Dy 3+ cations and two equatorial S 2 fragments. The nitride [(DyI) 3 N 2 ] in THF does not interact with sulfur but upon addition of triiodide DyI 3 the reaction affords cluster 2 in moderate yield.

The reduction of 1,2-bis[(2,6-diisopropylphenyl)imino]acenaphthene (dpp-bian) with an excess of europium metal in 1,2-dimethoxyethane (dme) produces a divalent europium complex with the dpp-bian dianion, [(dpp-bian)Eu(dme)2] (1). The reactions of 1 with phenyl-acetylene and camphor proceed via protonation of the diimine ligand to form the monomeric amido-amino complexes of divalent europium — [H(dpp-bian)Eu(C≡CPh)(dme)2] (2) and [H(dpp-bian)Eu(camphor)(dme)2] (3), respectively. Compounds 2 and 3 were characterized by IR spectroscopy and elemental analysis. Their molecular structures were determined by X-ray diffraction. Compounds 2 and 3 were shown to be monomeric seven-coordinate europium(ii) complexes with terminal phenylethynyl and enol ligands, respectively. According to the IR spectroscopic data, the terminal ligands in complexes 2 and 3 undergo tautomerization involving backward proton transfer from the amido-amino ligand to the substrate. The magnetic moment of compound 2 (8.03 μB) remains constant in the temperature range of 4—300 К and confirms the presence of divalent europium.

Neutral group-IV and rare-earth complexes stabilized by novel Cs and C1-symmetric 2-pyridylethylanilido ligands have been prepared and fully characterized before being scrutinized as catalyst precursors in the isoprene (IP) polymerization. In all the isolated complexes, these ligands coordinate to the metal centers in their monoanionic bidentate form. Tetra-amido ZrIV-complexes from this series (11 and 12) have shown only negligible catalytic activity in the IP polymerization, giving polydienes in traces, irrespective of the activator(s) and reaction conditions used. On the other hand, ternary systems made of a bis-alkyl rare-earth metal complex (13–16), an organoborate and a 10-fold excess of an aluminum-alkyl [pre-catalyst/Al-alkyl/borate = 1 : 10 : 1] are found to initiate the living IP polymerization with complete monomer conversion within a few minutes. The process selectivity has been investigated from different perspectives, analyzing its dependence from the rare-earth metal ion of choice (YIIIvs. LuIII), the ligand type (C1vs. Cs) and the activator(s). Polyisoprenes (PIPs) with a prevalent cis-1,4-motif (up to 67.0%) or mainly featured by vinyl pendant arms in their microstructure (up to 75.7% – 3,4-motif) are obtained.

The half-sandwich tetra-tert-butylcarbazol-9-yl iodo complex [(tBu(4)Carb)Sm(m-I)(THF)(2)](2) (1) was synthesized by the salt metathesis reaction of tBu(4)CarbK and SmI2(THF)(2) in THF. Complex 1 along with metallic Cu was also isolated from the oxidation reaction of (tBu(4)Carb)(2)Sm by CuI. The formation of stable radical tBu(4)Carb(center dot) was detected in this non-conventional process, indicating preferential oxidation of anion tBu(4)Carb(-) vs. Sm-II. The treatment of 1 with two equivalents of dibenzo-18-crown-6 resulted in heterolytic dissocia-tion of a h 5-bond Sm-tBu(4)Carb and afforded an ionic compound [tBu(4)carb(-)][SmI(crown)(THF)(2)](+) (4). Alkylation of 1 with o-NMe2C6H4CH2K (1: 2 molar ratio) in THF allowed for the synthesis of half-sandwich SmII alkyl complex (tBu(4)Carb) SmCH2(o-NMe2C6H4CH2)(THF)(2) (5) in 55% yield. The amido complex (tBu(4)Carb) SmN(SiMe3)(2)(DME) (6) was obtained by the reaction of 1 with two molar equivalents of NaN(SiMe3)(2) in THF in 89% yield.

A reaction of anhydrous yttrium chloride with an equimolar amount of lithium amidinateamidopyridinate obtained in situ by metallation of N,N’-bis(2,6-dimethylphenyl)-N-{6-[(2,6-dimethylphenyl)amino]pyridin-2-yl}acetimidamide ((2,6-Me2C6H3)NH(2,6-C6H3N)N(2,6-Me2C6H3)C(Me)=N(2,6-Me2C6H3), L1H) (1) with n-butyllithium in THF at–70 °C was used to synthesize the yttrium dichloride complex (L1)YCl2(THF)2 (2). The lutetium bis(alkyl) complex, namely, N’-(2,6-diisopropylphenyl)-N-(2,6-dimethylphenyl-N-{6-[(2,6-dimethylphenyl)amido]pyridin-2-yl}acetimidoamidinatebis(trimethylsilylmethyl)lutetium (4), was obtained by the reaction of N’-(2,6-diisopropylphenyl)-N-(2,6-dimethylphenyl)-N-(6-((2,6dimethylphenyl)amino)pyridin-2-yl)acetimidamide ((2,6-Me2C6H3)NH(2,6-C6H3N)N-(2,6-Me2C6H3)C(Me)=N(2,6-Pr 2 i C6H3), L2H (3)) with an equimolar amount of Lu(CH2SiMe3)3(THF)2. Complex 4 was found to be very stable and did not show indications of C—H-activation and other kinds of disintegration in benzene or toluene solution even upon prolonged heating at 60 °C. The reaction of complex 4 with an equimolar amount of 2,6-diisopropylaniline in toluene solution at room temperature led to the formation of the lutetium alkyl-anilide complex (L2)Lu(CH2SiMe3)(NH-2,6-Pr 2 i C6H3) (5). A three-component system 4—AlBu 3 i —[X][B(C6F5)4] ([X] = [Ph3C], [PhNHMe2], the molar ratio of 1: 10: 1) was found to catalyze polymerization of isoprene.

The new bis-o-iminobenzosemiquinonate nickel and cobalt complexes (imSQt-Bu)2M (M = Ni (1), Co (2)), where imSQ is a radical anion of 4,6-di-tert-butyl-N-(tert-butyl)-o-iminobenzoquinone, were synthesized and characterized in detail. The molecular structures of 1 and 2 have been established by single-crystal X-ray analysis. The metal atoms in 1 and 2 have a distorted tetrahedral environment, and the dihedral angles between the planes of two radical imSQ ligands are approximately 80° in both complexes. According to the structural and spectroscopy data along with magnetic susceptibility measurements the electronic structure of the complexes should be interpreted definitely as a high spin metal center NiII (d8, S = 1) in 1 and CoII (d7, S = 3/2) in 2 bonded with two o-iminobenzosemiquinonate radicals (Srad = 1/2). The strong antiferromagnetic metal–ligand spin interactions in both complexes lead to the observed St = 0 and St = 1/2 ground states in 1 and 2, respectively. The computational DFT UB3LYP/6-311++G(d,p) studies performed on 1 and 2 are in good agreement with experimental data. Complexes 1 and 2 have similar electrochemical properties. The electrochemical reduction of the complexes includes two quasi-reversible one-electron-transfer waves in the cathodic region corresponding to the formation of the anions [M(AP)2]2− and [(imSQ)M(AP)]1− (AP – dianion of 4,6-di-tert-butyl-N-(tert-butyl)-o-iminobenzoquinone), while in the anodic region only one quasi-reversible redox process was registered. All redox processes are shown to be ligand-based.

Three new 3D metal–organic frameworks of lanthanum based on mixed anionic ligands, [(La2(pQ)2(BDC)4)·4DMF]n, [(La2(pQ)2(DHBDC)4)·4DMF]n, [(La2(CA)2(BDC)4)·4DMF]n (pQ—dianion of 2,5-dihydroxy-3,6-di-tert-butyl-para-quinone, CA—dianion of chloranilic acid, BDC-1,4-benzenedicarboxylate, DHBDC-2,5-dihydroxy-1,4-benzenedicarboxylate and DMF-N,N′-dimethylformamide), were synthesized using solvothermal methodology. Coordination polymers demonstrate the rare xah or 4,6T187 topology of a 3D framework. The homoleptic 2D-coordination polymer [(La2(pQ)3)·4DMF]n was obtained as a by-product in the course of synthetic procedure optimization. The thermal stability, spectral characteristics and porosity of coordination polymers were investigated.

3a,6a-Diaza-1,4-diphosphapentalene (DDP, 1), in contrast to common azaphospholes, readily reacts with polyhalohydrocarbons with the formation of 1,1- or 1,4-addition products at the phosphorus atoms. Dibromomethane gives the substitution product of two bromine atoms [CH2(DDP)2]Br2 (2) and diphosphine (DDP-DDP)Br2 (3) containing a bridging bromine atom. In the course of the reaction of DDP with CF2Br2, two products of sequential substitution of the bromine atoms were isolated, which are 1,4-Br2(DDP) (6) and [CF2(DDP)2]Br2 (7). Tris(pentafluorophenyl)phosphine reacts with DDP at the C—F bond with the formation of 1,1-addition product 8. Compounds 2, 3, 7, and 8 contain hypervalent (tervalent 4-coordinated) phosphorus atoms. X-ray diffraction data indicate that the mutual arrangement of the DDP fragments in compounds 2, 3, and 7 is determined by the non-covalent interaction of one of the bromine atoms simultaneously with two phosphorus atoms of different DDP fragments in such a way that the lines of the N—P bonds converge at this bromine atom.

A reaction of Sc, Y, and Yb amidopyridinate dichlorides with the corresponding amount of LiCH2SiMe3 was used to synthesize bis(trimethylsilylmethyl) complexes (Ap)Ln(CH2SiMe3)2-(THF) (Ap is N-mesityl-6-(2,4,6-triisopropylphenyl)pyridine-2-amide (Ap9Me), Ln = Y (2); Ap is N-(2,6-diisopropylphenyl)-6-(2,4,6-triisopropylphenyl)pyridine-2-amide (Ap*), Ln = Sc (3), Yb (4)). An exchange reaction of yttrium amidopyridinate dichloride derivative 1 with 4 equiv. of ButLi in hexane gave the corresponding di-tert-butyl derivative Ap9MeY(But)2(THF) (5). Molecular structures of complexes 3 and 4 were established by X-ray diffraction. A method of the ligand solid angles was used to calculate the completion degree of the metal atom coordination sphere for the series of isomorphic derivatives (Ap*)Ln(CH2SiMe3)2(THF) containing the central metal ions with different ionic radii (Sc, Y, Yb, Lu). According to this method, the amidopyridinate ligand solid angle in these complexes virtually does not vary, while the solid angles of coordinated THF molecule and alkyl ligands vary within a wide range.

1,4-Dichloro-3a,6a-diaza-1,4-diphosphapentalene reacts with sodium acetylacetonate to form an adduct of diacylcarbene with trivalent dicoordinated phosphorus. In solution this adduct dimerizes according to the head-to-head type. The phosphorus atoms undergo transformation from the hypervalent state (in the adduct), in which the lone electron pair on the phosphorus atom is not involved in the formation of additional bonds with this phosphorus(III) atom, to the pentavalent pentacoordinated and trivalent tricoordinated state (in the dimer).

A reaction of digallane [(dpp-bian)Ga—Ga(dpp-bian)] (1) (dpp-bian is the 1,2-bis[(2,6-disopropylphenyl)imino]acenaphthene) with one equivalent of I2 leads to oxidation of (dpp-bian)2– in compound 1 to (dpp-bian)–and gives [(dpp-bian)GaI—GaI(dpp-bian)] (2). In the reaction of compound 2 with two equivalents of (acac)Na, not only exchange of the iodide and acetylacetonate ions takes place, but also a transfer of electrons from the metal—metal bond to dpp-bian with the formation of the complex [(dpp-bian)Ga(acac)] (3), in which the dpp-bian ligand is a dianion. A reaction of digallane 1 with 2,2´-bipyridyl at 200 °C in toluene in a sealed tube leads to the reduction of 2,2´-bipyridyl and gives the complex [(dpp-bian)Ga(bipy)] (4), which contains two different chelate redox-active ligands. The new compounds were characterized by IR (3, 4), NMR (3), and ESR spectra (4), the structures of both derivatives were established by X-ray diffraction.

The reactions of bis(pyrazolyl)methanes CH2(C3HN2R2-3,5)2 (R = Me, tBu) with Y(CH2SiMe3)3(THF)2 and LY(CH2SiMe3)2(THF)n (L = amidopyridinate (Ap′), amidinate (Amd), tridentate amidinate bearing 2-methoxyphenyl pendant in a side arm (AmdOMe) and pentamethylcyclopentadienyl (Cp*); n = 0, 1) were investigated. CH2(C3HN2tBu2-3,5)2 turned out to be inert in these reactions, while less bulky CH2(C3HN2Me2-3,5)2 easily undergoes metalation by yttrium alkyls. The reaction of Y(CH2SiMe3)3(THF)2 with CH2(C3HN2Me2-3,5)2 regardless of the molar ratio of the reagents affords a homoleptic tris(alkyl) species, Y[CH(C3HN2Me2-3,5)2]3 (1). However, the reactions of equimolar amounts of LY(CH2SiMe3)2(THF)n and CH2(C3HN2Me2-3,5)2 occur selectively with replacement of a sole CH2SiMe3 fragment and afford the related heteroalkyl complexes LY(CH2SiMe3)[CH(C3HN2Me2-3,5)2](THF)n (L = Ap′, n = 1 (6); Amd, n = 0 (7); AmdOMe, n = 1 (8); Cp*, n = 1 (9)) in good yields. The second equivalent of CH2(C3HN2Me2-3,5)2 does not react with het...

A reaction of o-N,N-dimethyltoluidine lithium derivative (o-Me2NC6H4CH2Li) with carbodiimides (RN=C=NR, where R = Pri, Cy) in THF at room temperature leads to lithium complex of the general formula [{o-Me2NC6H4CH2C(NR)2}Li(THF)2]2 (R = Pri (1), Cy (2)) containing a new tridentate amidinate ligand. X-ray diffraction studies showed that complexes 1 and 2 are dimeric due to the coordination of the nitrogen atoms of the amidinate group with different lithium atoms. The nitrogen atoms of the aminobenzyl fragment are not involved in the complexation. The exchange reactions of Y(BH4)3(THF)3 with lithium amidinates 1 and 2 carried out with the equimolar ratio of reagents in solution in THF proceeded with the formation of neutral amidinatebisborohydride complexes of the general formula [o-Me2NC6H4CH2C(NR)2]Y(BH4)2Ln (3: R = Pri, L = DME (with added DME), n = 1; 4: R = Cy, L = THF, n = 2). According to the X-ray diffraction data, compounds 3 and 4 are monomeric, borohydride ligands are coordinated to the rare-earth metal atom by the η3- and η2-type. The donor NMe2 groups of the amidinate ligands are not involved in the metal—ligand interaction. Yttrium complexes 3 and 4 exhibit catalytic activity in polymerization of rac-lactide and isoprene.

Synthesis and single-crystal X-ray diffraction study (SC-XRD) of the O,N-heterocyclic germylene Ge(PhAp) (1) containing chelate 4,6-di-tert-butyl-N-phenyl-o-amidophenolate ligand (PhApH2, where Ap – o-amidophenolate) are reported. Germylene 1 demonstrates a monomeric structure in contrast to earlier known related stannylene Sn(PhAp) (2) existing as a dimer. Diverse weak intermolecular interactions (Ge…Ge, CH…π(chelate) and Ge…π(arene)) were detected in the crystal packing of germylene 1. Hirshfeld surface analysis has been performed to evaluate such interactions. Reactivity of compounds 1 and 2 towards dithiodiiron hexacarbonyl has been examined. Low-valent germanium(II) and tin(II) centers are readily inserted into S-S bond of dithiodiiron hexacarbonyl with the formation of Fe4(µ4-ES4)(CO)12 (E: Ge(3); Sn(4)) and bis-ligand complexes of tetravalent metals E(PhAp)2. The resulting germanium(IV) and tin(IV) bis-o-amidophenolates were isolated as six-coordinated pyridine adducts E(PhAp)2(Py)2 (E: Ge(5); Sn(6)). All complexes were characterized by SC-XRD.

The basic physicochemical properties and molecular structure of bis-(thrimethylsiloxy). phthalocyaninato silicon [SiPc(OSiMe3)2] are investigated. The temperature of melting of this complex was measured by the DSC method in the temperature interval 20–520 °C (Tm =497 °C). Thermogravimetric analysis data showed mass loss occurs in the temperature range 275−500 °C. The mass loss in this temperature range is 96 %. Mass spectrometric studies of the composition of the gaseous phase of [SiPc(OSiMe3)2] was performed in the temperature range up to 450 °C. It was found that the complex is sublimated in monomeric form. The vapor pressure of the compound was determined as a function of temperature by the Knudsen effusion method. Based on the data obtained, the thermodynamic parameters of the sublimation process are calculated. The X-ray diffraction study revealed that molecular geometric parameters of [SiPc(OSiMe3)2] are varied slightly upon changing of temperature. The photovoltaic properties of [SiPc(OSiMe3)2] studied with heterojunction solar cell of configuration of ITO/complex /C60/Bphen/Al. The operating characteristics of the cell turned out comparable with the characteristics of earlier designed analogues devices based on phthalocyanine complexes of Cu, Zn and Sn.

Deprotonation of β-triketimines (2,6-Me2C6H3N = CMe)3CH (1), (2,6-Me2C6H3N = CMe)2CH(2-MeOC6H4N = CtBu) (2), (2,6-Me2C6H3N = CMe)2CH(2,6-Me2C6H3N = CtBu) (3) by equimolar amount of n-BuLi afforded lithium triketiminate complexes [(2,6-Me2C6H3N = CMe)3C]Li(THF) (4), [(2,6-Me2C6H3N = CMe)2C(2-MeOC6H4N = CtBu)]Li(THF)2 (5), [(2,6-Me2C6H3N = CMe)2C(2,6-Me2C6H3N = CtBu)]Li(THF)2 (6) in 70–80% yields. The salt metathesis reactions of LnCl3 (Ln = Y, Nd) with 6 lead to the formation of neutral triketiminate dichloro complexes [(2,6-Me2C6H3N = CMe)2C(2,6-Me2C6H3N = CtBu)]LnCl2(THF)2 (Ln = Y (7), Nd (8)) in 78 and 70% yields, while the analogous reaction of YCl3 with 5 resulted in triketiminate yttrium chloro ate complex [(2,6-Me2C6H3N = CMe)2C(2-MeOC6H4N = CtBu)]Y(THF)Cl(µ2-Cl)2Li(THF)2 (9). The reactions of the potassium derivatives of the related triketimines 2, 3 with YbI2(THF)2 resulted in the formation of mononuclear triketiminate iodo Yb(II) complexes [(2,6-Me2C6H3N = CMe)2C(2-MeOC6H4N = CtBu)]YbI(THF)2 (10) and [(2,6-Me2C6H3N = CMe)2C(2,6-Me2C6H3N = CtBu)]YbI(TMEDA) (11). X-ray analysis revealed that in 4 and rare-earth metals complexes 7–11 the monoanionic β-triketiminate ligands [(2,6-Me2C6H3N = CMe)3C]−, [(2,6-Me2C6H3N = CMe)2C(2-MeOC6H4N = CtBu)]−, [(2,6-Me2C6H3N = CMe)2C(2,6-Me2C6H3N = CtBu)]− feature bidentate coordination mode and are coordinated to a metal center only through two nitrogen atoms. The ternary systems 7–9/AliBu3/[CPh3][B(C6F5)4] exhibit catalytic activity in isoprene polymerization, allowing to carry out polymerization of 1000 equivalents in 2 h with 91–100% conversion. The obtained polyisoprenes feature high molecular weights (Mn = 12.8 × 104–20.2 × 104) and moderate polydispersities (Mw/Mn = 2.7–3.6), however excellent control of regio- and stereoselectivities (up to 9.9% cis-1,4 units) was observed.

Four novel binuclear high spin manganese(II), iron(II), cobalt(II) and nickel(II) complexes containing 1,2-bis(pyridin-2-ylmethylene)-para-phenylenediamine as a bridging ligand have been synthesized and investigated. Molecular structures of manganese and cobalt complexes were established by single crystal X-ray structural analysis. For all the complexes the magnetic susceptibility measurements have been performed. According to the obtained magnetic data the energies of intramolecular magnetic exchange interactions strongly depend on the electron structure of metal ion. In addition, all the obtained complexes demonstrate very weak antiferromagnetic metal-metal interaction.

Treatment of (dpp-Bian)Ga–Ga(dpp-Bian) (1) (dpp-Bian = 1,2-bis[(2,6-diisopropylphenyl)imino]acenaphthene) with iodine gives (dpp-Bian)Ga(I)–Ga(I)(dpp-Bian) (2), which reacts in situ with K(C5H4CH2CH2NMe2) (KCpDo) or K(OCH2CH2NMe2) (KORDo) to produce the monomeric species (dpp-Bian)GaCpDo (3) and (dpp-Bian)GaORDo (4), respectively. Complex 3 reacts with PhC≡CH to give the paramagnetic derivative (dpp-Bian)Ga(C≡CPh)2 (5), while compound 4 is inert toward this alkyne. In contrast, monomeric (dpp-Bian)Ga(S2CNMe2) (6) reacts with PhC≡CH and HC≡CH to give the cycloaddition products [dpp-Bian(PhC═CH)]Ga(S2CNMe2) (7) and [dpp-Bian(HC═CH)]Ga(S2CNMe2) (8). The related compounds [dpp-Bian(MeC═CC(O)OMe)]Ga(S2CNMe2) (9) and [dpp-Bian(CH2CH═C(Me)O)]Ga(S2CNMe2) (10) have been obtained in the reactions of complex 6 with methyl 2-butynoate and methyl vinyl ketone, respectively. New complexes have been characterized by 1H NMR (3, 4, and 7–10) and ESR (5) spectroscopy; their molecular structures have been established by sin...

Reduction of 1,2-bis[(2,6-diisopropylphenyl)imino]acenaphthene (dpp-bian, 1) with metallic europium in 1,2-dimethoxyethane (dme) under anaerobic conditions gave a europium(II) complex with the acenaphthene-1,2-diimine dianion, (dpp-bian)Eu(dme)2 (4), in high yield. Oxidation of complex 4 with triphenyltin chloride or 1,2-dibromostilbene afforded the corresponding halogen derivatives [(dpp-bian)Eu(µ-Cl)(dme)]2 (5) and [(dpp-bian)Eu(µ-Br)(dme)]2 (6). The molecular structures of complexes 4–6 were determined by X-ray diffraction. The magnetic moments of complexes 5 and 6 remain constant over a temperature range from 25 to 295 K; they are indicative of the presence of the europium(II) ion and the dpp-bian radical anion in both the complexes.

Bis-amido TiIV and ZrIV complexes stabilized by ansa bis(amidinate) ligands {C6H4-1,2-[NC(tBu)N(2,6-R2C6H3)]2?M(NMe2)2 [M = ZrIV, R = Me (3), R = iPr (4); M = TiIV, R = Me (5), R = iPr (6)] and ?C6H4-1,2-[NC(tBu)N(2,6-Me2C6H3)]2}Zr(NMe2)3H (3?HNMe2) were prepared in fairly good yields by reacting a (bis)amidine ligand [C6H4-1,2-{NC(tBu)N(2,6-R2C6H3)H}2 [R = Me (1), iPr (2)] with an equimolar amount of the metal precursor [M(NMe2)4 (M = ZrIV, TiIV)]. The salt metathesis reaction between an equimolar amount of sodium amidinates ?C6H4-1,2-[NC(tBu)N(2,6-R2C6H3)]2Na2? and ZrCl4(thf)2 was also scrutinized to synthesize the corresponding ZrIV bis(amidinate) dichlorides ?C6H4-1,2-[NC(tBu)N(2,6-R2C6H3)]2?ZrCl2 [R = Me (7), iPr (8)]. The ligands coordination mode to MIV ions was found to be strongly affected by the steric hindrance of the amidinate ligands (Me vs. iPr substituted aniline moieties) as well as by the nature of the ancillary groups bound to the metal center (NMe2 vs. Cl). Bis(amido) ligands with the 2,6-Me2C6H3 substituents at the amidinate nitrogens coordinate the zirconium ion in a tetradentate fashion both in solution and in the solid state (3 and 3?HNMe2). Compounds containing the bulkier 2,6-iPr2C6H3 units prefer a tridentate coordination mode (4). With the smaller TiIV ion, all the bis(amidinate) ligands from this series are tridentate in the solid state (compounds 5 and 6) while they reversibly switch their denticity from tridentate to tetradentate (?3 vs. ?4) in solution depending on the temperature. The ZrIV complex 4, featuring with the bulkier bis(amidinate) ligand 2, shows a similar behavior to that of its TiIV analogue, with a tridentate ligand coordination at the solid state and a temperature induced denticity change in solution as a temperature function. Thermodynamic standard parameters for the ?3 vs. ?4 interconversion on the two model compounds 4 and 5 in toluene-d8 solution have been measured from the respective linear van't Hoff plots fitting. Finally, ZrIVbis(chloride) complexes 7 and 8 invariably show a tetracoordination mode of their bis(amidinate) ligands (1 and 2) both in solution and in the solid state.