Mikhail Shatruk

Synthesis and the crystal structure of [Hg6As4](InCl6)Cl: influence of covalent and electrostatic factors on the supramolecular structure

A new inorganic supramolecular complex [Hg6As4](InCl6)Cl was synthesized. The complex crystallizes in the cubic space group Pa3 with the unit cell parameter a = 12.109(1) Å and Z = 4. The crystal structure of the complex is based on the ∞3[Hg6As4]4+ three-dimensional cationic host framework. The guest InCl63– and Cl– anions are located in the cavities of the framework. The host—guest interactions were examined by quantum-chemical calculations of the equilibrium geometry of the InCl63– anion and analysis of the periodic zero-potential surface of the supramolecular complex. It was demonstrated that the electrostatic factors dominate over the covalent factors in the organization of the supramolecular structure of [Hg6As4](InCl6)Cl.

A series of complexes of the phosphorus-based TTF ligand o-P2 with the metal ions FeII, CoII, NiII, PdII, PtII, and AgI

Reactions of 3,4-dimethyl-3,4-bis(diphenylphosphino)tetrathiafulvalene, o-P2, with [BF(4)](-) salts of Fe(ii), Co(ii), Ni(II), Pd(II), and Pt(II) yield complexes of general formula [M(o-P2)(2)][BF(4)](2). Similar reactions between o-P2 and AgSbF(6) or AgPF(6) produced the salts [Ag(o-P2)(2)][X] where X = [SbF(6)](-) or [PF(6)](-). The resulting compounds were fully characterized by (1)H and (31)P{(1)H} NMR, infrared and electronic absorption spectroscopies, cyclic voltammetry, FAB-MS and single-crystal X-ray diffraction. The paramagnetic Co(II) compound exhibits an S = 3/2 state with large spin-orbit coupling contribution at higher temperatures and an effective S = 1/2 state below 20 K. Electrochemical studies of the compounds indicate that the two functionalized TTF ligands are not in electronic communication and that they essentially behave as isolated redox centers.

Structural and magnetic properties of iron(II) complexes with 1,4,5,8,9,12-hexaazatriphenylene (HAT).

Reactions of Fe(II) salts with the ligand 1,4,5,8,9,12-hexaazatriphenylene (HAT) led to the isolation and characterization of four new compounds: [Fe3(HAT)(H2O)12](SO4)3.3.3H2O (1), [Fe2(HAT)(SO4)(H2O)5](SO4).2H2O.CH3OH (2), [Fe2(HAT)(SO4)(H2O)5](SO4).3H2O (3), and [Fe3Cl5(HAT)(CH3OH)4(H2O)]Cl (4). Compound 1 crystallizes as a trinuclear cluster in which HAT acts as a tris-chelating ligand. Compounds 2 and 3 are two polymorphs of an infinite one-dimensional structure in which the Fe atoms are coordinated to HAT and then connected into the chain through bridging sulfate anions. Compound 4 exhibits a similar chain structure, but with bridging chloride ligands. The magnetic behavior of the new compounds is indicative of weak antiferromagnetic coupling between the Fe(II) centers through the HAT ligand.

Unexpected conversion of a hexacyanometallate to a homoleptic nitrile complex with triphenylborane substituents

The homoleptic, triphenylborane adduct of the hexacyanochromate anion was structurally characterized and found to be a product in which all six cyanide ligands have undergone isomerization to nitrile groups.