卷 43, 编号 9 (2017)

Bis(4-bromophenoxy)tris(para-tolyl)antimony (I), bis(4-nitrophenoxy)tris(para-tolyl)antimony (II), bis(4-nitrophenoxy)tris(4-fluorophenyl)antimony (III), bis(2,3,4,5,6-pentafluorophenoxy)tris(4-fluorophenyl) antimony (IV), and bis(2,3,4,5,6-pentachlorophenoxy)tris(4-fluorophenyl)antimony (V) (CIF files CCDC 1470829 (I), 1474589 (II), 1062337 (III), 1470476 (IV), and 1472954 (V)) are synthesized in high yields by the reactions of tris(para-tolyl)- and tris(4-fluorophenyl)antimony with 4-bromo-, 4-nitro-, 2,3,4,5,6-pentafluoro-, and 2,3,4,5,6-pentachlorophenol, respectively, in diethyl ether in the presence of tert-butyl hydroperoxide. The Sb atoms in compounds I–V have a distorted trigonal bipyramidal coordination with the aroxy groups in the axial positions (angles OSbO 174.08(11)°–179.4(5)°). The average Sb–C bond lengths in compounds I–V are similar and independent of the nature of the para-substituent in the aryl rings. The Sb–O distances are close to the sum of covalent radii of Sb and O atoms. Hydrogen bonds H···F are involved in the formation of the crystal structures of compounds III–V.

The electrochemical oxidation of the chromium(III) and indium(III) complexes with 3,6-di-tert-butyl-o-semiquinolate leading to the formation of active monocationic species is studied by cyclic voltammetry. The reactions of the latter with hydrogen sulfide generate the radical cation of H₂S, whose fragmentation affords the proton and thiyl radical. These complexes are proposed for the first time as redox mediators for the one-pot thiolation of inert cycloalkanes C₆–C₈, which decreases the activation energy of hydrogen sulfide compared to that for direct electrochemical oxidation. The major products of cycloalkane functionalization involving H₂S are thiols and organic di- and trisulfides. The yield of the synthesized compounds depends on the type of the mediator: the chromium(III) complex exhibits the highest efficiency in the electrocatalytic transformations.

Two Co(III) dioximates, cyanoguanidine complex {[Na₂(µ-H₂O)₂(L¹)₂(H₂O)₂]-[Co^III(DmgH)₂(N₃)₂]}_n[Co^III(DmgH)₂(N₃)₂]_n (L¹ = (H₂N)₂C=N–C=N) (I) and aminoguanidine complex [H₃L²][Co(DmgH)₂(N₃)₂] (H₂L² = H₂N–C(=NH)–NH–NH₂) (II), were synthesized from the [CoCl(DmgH)₂(H₂O)] structural unit (DmgH^– is the dimethylglyoxime monoanion). The implementation of the synthesis was confirmed by chemical analysis, IR spectroscopy, and X-ray diffraction (CIF files CCDC 1531845 (I), 1531846 (II)). Both compounds are ionic. Compound I consists of cations representing centrosymmetrical 2D coordination polymers, {[Na₂(µ-H₂O)₂(L¹)₂(H₂O)₂][Co^III(DmgH)₂(N₃)₂]}ⁿ⁺_n, and monomeric [Co(DmgH)₂(N₃)₂]^– anions, while in II, the charge of the [Co(DmgH)₂(N₃)₂]^– complex anion is counterbalanced by the organic [H₃L²]⁺ cation. In I, L¹ is coordinated to the metal as a monodentate neutral ligand, while in II, H₂L² occurs in the complex as a protonated uncoordinated component. Since L¹ in I and H₂L² in II contain functional amine groups able to form intermolecular hydrogen bonds acting as proton donors, the component packing mode in the crystals was analyzed assuming various types of interactions, apart from electrostatic ones. The biological properties of the complexes were tested considering their effect on the biosynthesis of proteases by the micromycete Fusarium gibbosum CNMN FD 12 strain. Culturing the producer on a culture medium containing complex I in the selected optimal concentrations of 5–10 mg/L was found to increase the acid protease activity by 140–150%.

A Eu-based luminescent MOF, namely, {[Eu(µ₃-HPhIDC)(µ₂-C₂O₄)_0.5(H₂O)] · 2H₂O}_n (I) (H₃PhIDC = 2-phenyl-1H-imidazole-4,5-dicarboxylic acid) has been hydrothermally synthesized and structurally characterized by single-crystal X-ray diffraction techniques (CIF file CCDC no. 1457365). The MOF I indicates characteristic sharp emission bands of Eu³⁺ ion, which is selectively sensitive to nitrobenzene- based derivatives (nitrobenzene, 2-nitrotoluene, 3-nitrotoluene, 1,3-dinitrobenzene and 2,4-dinitrotoluene). These properties make I a potential fluorescence sensor for these chemicals.