Two new heteroleptic cobalt(II) complexes (3,6-Cat)Co(R-DAD) (where (3,6-Cat)2− is a dianion of 3,6-di-tert-butyl-o-benzoquinone, R-DAD is diisopropyl-1,4-diaza-1,3-butadiene (R = i-Pr (1)) or dicyclohexyl-1,4-diaza-1,3-butadiene (R = c-Hex (2)) have been synthesized and characterized in detail by IR, UV–Vis–NIR spectroscopy, and elemental analysis. The molecular structure of 1 was determined by X-ray diffraction analysis. Magnetic properties of 1 and 2 were measured both in a solid state and in a solution. According to the single-crystal X-ray diffraction analysis, the metal ion in 1 has a planar coordination environment, but magnetic susceptibility measurements of the microcrystalline samples of 1 and 2 indicate the formation of both forms with tetrahedral (d7, h.s., SCo = 3/2) and planar (d7, l.s., SCo = ½) coordination environments of the metal ion. Absorption spectra of crystalline samples of 1 and 2 possess intense absorption band in the NIR region. Electrochemical measurements of 1 and 2 were also performed.

A series of dimethylindium complexes of general formula (R-ONN)InMe2 (R = H (1), Me (2), Cl (3), NO2 (4)) have been synthesized by the reaction of Me3In with an appropriate...

Reactions of Schiff base ligands HL1-4 (wherein HL1 is 2-((pyridin-4-ylmethylene)amino)phenol, HL2 is 4-methyl-2-((pyridin-4-ylmethylene)amino)phenol, HL3 is 4-chloro-2-((pyridin-4-ylmethylene)amino)phenol, HL4 is 4-nitro-2-((pyridin-4-ylmethylene)amino)phenol) with Me3In in a molar ratio of 1:1 lead to the formation of dimethylindium complexes of the general formula (L1-4)InMe2 (1-4). The molecular structures of 1-4 have been determined by single crystal X-ray analysis. In the crystal, all complexes form centrosymmetric dimers via coordination of bridging mu 2-O atoms of the phenolate fragment to the metal atom of the neighboring molecule. The crystal packing of 1-4 represents infinite chains due to short contacts between each indium in the dimer and the pyridine nitrogen of the adjacent dimeric molecule. UV-vis absorption spectra of 1-4 have been recorded in various organic solvents. The position of the absorption band assigned to intraligand charge transfer (ILCT) in the UV-vis absorption spectra of 1-4 depends on the nature of the substituent in the phenolate moiety of L1-4 and shifts hypsochromically with increasing of the electron acceptor properties of the substituents in the Schiff bases. The HOMO-LUMO energy gap calculated from the CV measurements for 1-3 also narrows with the introduction of the electron donor substituents in the ligand L. All complexes show fluorescence with broad emission bands in the range of 500-700 nm both in Me-THF solution and in the solid state.

Six new coordination polymers (CPs) of cadmium based on an extended anilate-type ligand, 4,4 '-(1,4-phenylenebis(azanylylidene))bis(3,6-di-tert-butyl-2-hydroxycyclohexa-2,5-dienone) (H2L), have been synthesized. The series of coordination polymers includes [Cd(L)(DMF)] (1), 1D-CP [Cd(L)(dipy-1)]2DMF (2A) and 2D-CP [Cd(L)(dipy-1)]DMF (2B), [Cd2(L)2(dipy-2)(DMF)2] (3), [Cd(HL)(CH3COO)(dabco)] (4) and [Cd(L)(ur)2](H2L) (5) (where L - deprotonated form of H2L, DMF - N,N '-dimethylformamide, dipy-1 - 4,4 '-trimethylenedipyridine, dipy-2 - 4,4 '-dipyridyl, dabco - 1,4-diazabicyclo[2.2.2]octane, ur - urotropine). The crystal structure and thermal decomposition of 1D- and 2D-coordination polymers are reported. The structural diversity of the synthesized compounds was found to depend on the additional neutral donor ligands in the cadmium coordination sphere. Thus, the introduction of the flexible N-donor ligand dipy-1 into the cadmium coordination sphere leads to the formation of two types of coordination polymers (1D and 2D). The use of the rigid ligand dipy-2 promotes the formation of "honeycomb" 2D-CPs. The use of shorter N-donor ligands dabco and ur leads to linear derivatives in which the ligands being coordinated by cadmium don't act as "crosslinkers" of the chains in the network. The extended anilate ligand is an excellent platform for designing MOFs with diverse structures and topologies.

New manganese(II) and nickel(II) 1-D zigzag coordination polymers [M 2+ (pQ 2− )·2(solv)] n (M 2+ = Mn 2+ , solv = N,N’-dimethylacetamide ( 1 ) and M = Ni 2+ , solv = N,N’-dimethylformamide ( 2 ); pQ 2− - dianionic form of 2,5-di-hydroxy-3,6-di- tert -butyl-para-quinone) have been synthesized and characterized. Both compounds 1 and 2 are isomorphic. Their physicochemical properties such as thermal stability, gas sorption, redox and magnetic properties are described.

A six-coordinated indium(III) complex (APMe)(imSQMe)In(bipy) (1), bearing two types of redox-active ligands—mono- (imSQMe) and dianion (APMe) of 4,6-di-tert-butyl-N-(2,6-dimethylphenyl)-o-iminobenzoquinone and 2,2′-bipyridyl—was synthesized and characterized in detail. The intense, well-resolved ESR spectrum of 1 in dichloromethane solution clearly indicates the spin density delocalization between both AP and imSQ ligands. The UV-vis spectrum of 1 possesses an absorption band in the NIR region. The molecular structure of compound 1 was established by single-crystal X-ray diffraction analysis.

Two monomeric heteroleptic charge transfer (CT) complexes NiII(3,6-Cat)(DADdipp) (1) and CoII(3,6-Cat) (DADdipp) (2) of "& alpha;-diimine-MII-catecholate" general type were prepared in the course of two-step synthetic procedures, based on 3,6-di-tert-butyl-o-benzoquinone (3,6-DTBQ) and 1,4-bis(2,6-di-isopropylphenyl)-1,4-diaza-1,3-butadiene (DADdipp). Square-planar coordination environment in complex 1 enables an implementa-tion of a low energy ligand-to-ligand charge transfer (LL'CT), thus making NIR NiII chromophore (& lambda;max = 1107 nm, in toluene) with high absorptivity of light and a fine sensitivity of CT energy towards solvent polarity (red solvatochromic shift from CH3CN to toluene at 192 nm). Energy of frontiers orbitals and HOMO-LUMO gap of 1 is evaluated in synergy of UV-vis-NIR spectroscopy, cyclic voltammetry, and DFT calculations, with a good accordance of data sets. A significant ligands' bulkiness provided a tetrahedral distortion of square-planar N2O2 polyhedron of 2 in solutions (CH3CN, CH2Cl2, THF, toluene), that changed CT nature drastically with a concomitant decrease of absorptivity and an elimination of solvatochromism. Electrochemical behavior of studied complexes is defined by the differences in geometry of a coordination environment and corresponding mutual arrangement of metal and ligand orbitals (in solution): one-electron redox processes of square-planar NiII derivative 1 are predominantly ligand-centered, while redox transitions in tetrahedral CoII complex 2 proceed with the substantial participation of cobalt center.

The five-coordinated gallium(III) complex (AP Me )GaI(bipy) (1) , bearing two types of redox-active ligands, namely, the 4,6-di- tert -butyl- N -(2,6-dimethylphenyl)- o -iminobenzoquinone dianion (AP Me ) and 2,2′-bipyridyl along with an iodine atom in the coordination sphere, was synthesized and characterized in detail. The molecular structure of compound 1 established by single-crystal X-ray diffraction analysis. Compound 1 is stable in the crystalline state in the absence of atmospheric oxygen and moisture; however, it undergoes decomposition in solution due to symmetrization. The color of complex 1 was found to differ essentially in crystals and in solution. The observed effect is due to possible intermolecular charge transfer in the crystalline state.

Copper(II) catecholate complexes based on 3,6-di- tert -butyl- o -benzoquinone with N-donor ligands of the phenanthroline series have been synthesized: (3,6-Cat)Cu(Phen) ( I ), (3,6-Cat)Cu(DPQ) ( II ), and (3,6-Cat)Cu(DPPZ) ( III ), where 3,6-Cat is the 3,6-di- tert -butyl- o -benzoquinone dianion, Phen is phenanthroline, DPQ is dipyrido[3,2- d :2',3'- f ]quinoxaline, and DPPZ is dipyrido[3,2- a :2',3'- c ]phenazine. The synthesized copper(II) complexes demonstrate intramolecular ligand-to-ligand charge transfer responsible for their intense violet color. The electronic structure of the synthesized chromophores was studied by electronic spectroscopy, cyclic voltammetry, and quantum-chemical calculations. The molecular and crystal structures of the synthesized compounds were determined by X-ray diffraction analysis (CIF files CCDC 2 250 975 ( I ⋅THF), 2 250 976 ([( II ⋅THF)( II )]⋅3THF), 2250977 ( II )).

The article deals with the history of Russian manuscript tradition from the period since the end of the 17th – first half of the 18th century that is a version of the so-called European “popular literature.” These books were addressing mass audience interested in fictional literature, and contained secular and entertaining stories, mainly based on amorous adventures. Part of this Russian tradition was represented by translated novels, including the trend that might be aptly defined as “novels on Spanish princes.” This description is systematically used in the titles of corresponding texts, and that facts looks rather strange, considering almost total lack of knowledge of Spanish literature or language, or any contacts with Spain in the Russian culture of the time. Through the analysis of a number of these texts (“The Novel of Brun,” “The Story of Decoronij,” “The Story of Doltorn,” and several others), the author comes to a hypothetical explanation of the origin of this peculiar genre that becomes a specific appropriation of Spanishness in Russian literature.

Gallium(III) catecholates with bipyridine ligand [(3,5-Cat)Ga(bipy)2]I and (3,6-Cat)GaI(bipy) (Cat is di-tert-butylcatecholate) were synthesized and characterized by single-crystal X-ray diffraction. The appearance of near-infrared ligand-to-ligand charge transfer for pentacoordinate complex was observed.

A series of metal halide complexes with 9,10-phenanthrenequinone (PQ) have been synthesized and characterized in detail. An interaction of PQ with metal halides leads to molecular complexes with general formula (PQ)? MXn (MXn = ZnI2, CdI2, HgBr2, InI3). The molecular structures of these complexes have been established by single-crystal X-ray analysis. The metal type determines the resulting molecular structure: the reaction product of PQ with ZnI2 is neutral mononuclear complex ((PQ)? ZnI2 (1) or (PQ)(2)ZnI2 (2) depending on the synthesis conditions), CdI2 produces with PQ a 1D-coordination polymer [(PQ)? CdI2](n) (3), HgBr2 coordinates two PQ ligands with the formation of (PQ)(2)HgBr2 (4) while indium complex with PQ has an ionic nature [(PQ)(2)InI2](+)[InI4](-) (5). The instant reduction accompanies the reaction of PQ with MgI2 and GaI3; unstable monoradical species (PSQ)MgI and (PSQ)GaI2 (where PSQ is an anion-radical of PQ) have been detected using EPR spectroscopy.

A series of new charge transfer (CT) chromophores of “α-diimine-MII-catecholate” type (where M is 3d-row transition metals—Cu, Ni, Co) were derived from 4,4′-di-tert-butyl-2,2′-bipyridyl and 3,6-di-tert-butyl-o-benzoquinone (3,6-DTBQ) in accordance with three modified synthetic approaches, which provide high yields of products. A square-planar molecular structure is inherent for monomeric [CuII(3,6-Cat)(bipytBu)]∙THF (1) and NiII(3,6-Cat)(bipytBu) (2) chromophores, while dimeric complex [CoII(3,6-Cat)(bipytBu)]2∙toluene (3) units two substantially distorted heteroleptic D-MII-A (where D, M, A are donor, metal and acceptor, respectively) parts through a donation of oxygen atoms from catecholate dianions. Chromophores 1–3 undergo an effective photoinduced intramolecular charge transfer (λ = 500–715 nm, extinction coefficient up to 104 M−1·cm−1) with a concomitant generation of a less polar excited species, the energy of which is a finely sensitive towards solvent polarity, ensuring a pronounced negative solvatochromic effect. Special attention was paid to energetic characteristics for CT and interacting HOMO/LUMO orbitals that were explored by a synergy of UV-vis-NIR spectroscopy, cyclic voltammetry, and DFT study. The current work sheds light on the dependence of CT peculiarities on the nature of metal centers from various groups of the periodic law. Moreover, the “α-diimine-MII-catecholate” CT chromophores on the base of “late” transition elements with differences in d-level’s electronic structure were compared for the first time.

A series of new paramagnetic six-coordinate gallium complexes based on 3,6-di-tert-butyl-o-benzoquinone with N-donor ligands, such as pyridine (Py), 2,2′-dipyridyl (2,2′-dipy), and 4,4′-di-tert-butyl-2,2′-dipyridyl (But-dipy), were synthesized and structurally characterized. The molecular structures of the synthesized compounds were established by single-crystal X-ray diffraction. The complexes with bidentate N-donor ligands have the cis arrangement of the o-quinone ligands, whereas the compound with coordinated pyridine molecules has the trans arrangement of the diolate moieties. The synthesized compounds are characterized by spin density delocalization between the differently charged redox-active ligands. Regardless of the metal coordination environment, the near-IR region of the electronic absorption spectra of all the synthesized complexes show a low-intensity charge-transfer band between the catecholate and o-semiquinolate ligands, which was confirmed by DFT calculations.

Spin-crossover metal complexes represent important building blocks for a future generation of electronic and optical devices. Pentacoordinated o-iminosemiquinonate iron(III) complexes are able to demonstrate spin transitions between high spin (HS) and intermediate spin (IS) states under the influence of temperature or irradiation. Studied ((Me)imSQ)(2)FeBr sample showed a broad magnetic transition in the temperature region from 30 K to 300 K. Remarkably that observed behavior of magnetization can be interpreted with two controversial models. In the first model, the values of the effective magnetic moment at low temperature and high temperature can be assigned to the IS and HS magnetic moment of ferric ion coupled antiferromagnetically to radical anion ligands. In the second model, the metal spin on metal center remains IS in the whole temperature interval, while the mutual orientation of three magnetic moments in the molecule undergo changes due to exchange interactions. In this work we apply density functional theory and X-ray absorption spectroscopy to unravel the origin of magnetic properties of the complex. Temperature-induced changes of interatomic distances in the first coordination sphere support the second model. Such comprehensive analysis of the magnetic properties makes it possible to shed light on the nature of spin transitions in complexes of transition metals with open-shell ligands, which are often complicated by strong exchange interactions.