Russian Journal of Coordination Chemistry最新文献

New water-soluble copper(II) complexes with dicarboxylic acids were obtained by the heterogeneous reaction of copper hydroxy carbonate with succinic or fumaric acid in water at 50°C. The additional introduction of monoethanolamine (MEA) into the complexes ensured high solubility of copper succinate and fumarate. The structures of the complexes [Cu(Suc)·2MEA]·H₂O and [Cu(Fum)·2MEA]·H₂O were studied by X-ray diffraction (CCDC nos. 2352578 and 2352579, respectively). The compounds were found to have a polymeric structure composed of zigzag chains.

New charge-transfer complexes with pyrazine are synthesized from germanium(IV) and silicon(IV) bis(catecholates): 36Сat₂Ge, 35Cat₂Ge, and 36Сat₂Si (36Сat and 35Cat are 3,6- and 3,5-di-tert-butylpyrocatechol dianions, respectively). The synthesized compounds in the crystalline state are 1D coordination polymers with the octahedral environment of the complexing agent. The electronic absorption spectra of suspensions of the crystalline compounds in Nujol demonstrate an absorption in a range of 450–800 nm causing their intense color. A set of the spectral and theoretical studies indicates that the synthesized metal-organic frameworks of silicon and germanium can be considered as donor–acceptor chromophores with the photoinduced interligand charge transfer between the donor catecholate and acceptor pyrazine ligands.

The reaction of the mononuclear complex [PhenCu(OOC^tBu)₂(H₂O)] (I) with [PhenCu(CH₃CN)(Otf)₂] (Phen = 1,10-phenanthroline, Otf = CF₃S({text{O}}_{3}^{ - })) in dichloromethane at room temperature gave the binuclear complex [Phen₂Cu₂(µ-OOC^tBu)₂(Otf)₂] (II). The reaction of II with pyrazole (PzH) involved the displacement of the triflate anions to the outer sphere and gave the ionic complex [Phen₂Cu₂(µ-OOC^tBu)₂(PzH)₂](Otf)₂ (III), while a similar reaction with 3,5-bis(trifluoromethyl)pyrazole ((CF₃)₂PzH) was accompanied by its deprotonation and gave the heteroleptic complex [Phen₂Cu₂(µ-OOC^tBu)(µ-(CF₃)₂Pz)(µ-Otf)]Otf (IV). Compounds I–IV were characterized by X-ray diffraction (CCDC nos. 2332399 (I), 2332400 (II), 2332402 (III), and 2332401 (IV)), IR spectroscopy, and elemental analysis. According to X-ray diffraction data, the copper atoms in I–IV occur in a square pyramidal environment. The crystal packing of complexes I–III involves stacking interactions between phenanthroline molecules giving rise to supramolecular chains.

A series of copper(II), nickel(II), and cadmium(II) compounds with pivalate (Piv) or pentafluorobenzoate (Pfb) anions and 2-amino-1-methylbenzimidazole (L) molecules, [Cu₂(Piv)₄(L)₂]·2MeCN (I), [Ni(Piv)₂(L)₂][Ni(Piv)₂(L)₂(MeOH)] (II), and [Cd(Pfb)₂(L)₂] (III), were obtained. In the case of copper compounds, a binuclear complex with a Chinese lantern structure was formed, while nickel and cadmium salts resulted in the formation of mononuclear complexes. In all synthesized compounds, the 2-amino-1-methylbenzimidazole molecule is a monodentate ligand, coordinated to the metal atom via the nitrogen atom of the benzimidazole ring. The compounds were characterized by X-ray diffraction, IR spectroscopy, and CHN analysis.

The results of investigation of the heterometallic trinuclear {Zn₂Ln} and {Zn₂Ca} carboxylate coordination compounds are systematized in the review. The methods of the synthesis, structural peculiarities, and some physicochemical properties are discussed.

The tetranuclear complex H₂Ru₄(CO)₁₁(µ₄-η¹,η⁵-CC₅H₄) (I) was obtained by the photochemical reaction of Ru₃(CO)₁₂ with Z-1-(4-tolyl)-3-phenylaminoprop-2-en-1-one (λ ≥ 210 nm). The structure of complex I was established by single crystal X-ray diffraction. According to X-ray diffraction data, the complex is described by a superposition of resonance structures, that is, the carbene cluster YCRu₃, in which the substituent Y at the carbyne carbon atom is (η⁵-C₅H₄)Ru(CO)₂, and a vinylidene complex containing a fulvene form of the ligand, in which the exocyclic carbenium carbon atom is additionally stabilized by coordination to a triangular ruthenium cluster. For description of the interatomic binding in I, quantum chemical calculations of the electronic structure of the molecule in the gas phase were carried out at the PBE0/def2TZVP level. The features of binding of the organic ligand to the metal core were described in terms of the atoms in molecules theory. According to the calculations, the C₆H₄ moiety in I is a fulvene type ligand in which two hydrogen atoms in the CH₂ group have been replaced by ruthenium atoms.

Nonsymmetrical lithium β-diketonate (LiL) containing tert-butyl and acetal substituents at the dicarbonyl cage has been synthesized for the first time and is structurally characterized (CIF file CCDC no. 2364039 (I)). The reactions of functional lithium β-diketonate with salts of trivalent rare-earth metals in methanol afford heterobinuclear complexes [(LnL₃)(LiL)(MeOH)] (Ln = Eu, Gd, Tb). The structures of the complexes are characterized by X-ray diffraction (XRD) (CIF files CCDC nos. 2364040 (II), 2364041 (III), 2364042 (IV)).

The reactions of 10-(aryl)phenoxarsines (L¹ = 10-(4-tolyl)phenoxarsine, L² is 10-(4-fluorophenyl)phenoxarsine, L³ is 10-(3-fluorophenyl)phenoxarsine, and L⁴ is 10-(2-methoxyphenyl)phenoxarsine) with Pt(COD)Br₂ afford platinum(II) complexes [Pt(L^1–4)₂Br₂] (I–IV). The complexes are characterized by elemental analysis, IR spectroscopy, mass spectrometry, and NMR (¹Н, ¹³С, ¹⁹⁵Pt) spectroscopy. The Pt(II) complexes in solutions exist as two isomers mutually exchanging at a rate intermediate in the NMR time scale. The molecular structures of complexes cis-II·chloroform, trans-II, and cis-IV·dichloromethane are determined by XRD (CIF files CCDC nos. 2368769 (cis-II·chloroform), 2368770 (trans-II), and 2368771 (cis-IV·chloroform)). The platinum(II) dibromide complexes can crystallize as both cis and trans isomers. The study of the photophysical properties of the platinum(II) complexes shows that the trans isomers are characterized by emission in the orange spectral range, whereas the cis isomers almost does not luminesce. 10-(Aryl)phenoxarsines and their platinum(II) complexes are tested to cytotoxicity against the M-HeLa and HuTu 80 human cancer cell lines and hepatocyte-like cells of the Сhang liver line.

The reaction of the tetrahedral rhenium arsenide cluster K₈[{Re₄As₂(AsO)₂}(CN)₁₂] with molten KF·HF is studied. The reaction affords complex K₆[{Re₄As₂(AsO)F}(CN)₁₂]·3H₂O·KF (I). The substitution of one (µ₃-AsO)^3– ligand by µ₃-F^– is shown to occur during the reaction, and the remained internal ligands are not involved in the reaction. The phase purity of the synthesized compound and the absence of impurities of different compositions are confirmed by phase X-ray diffraction (XRD) and mass spectrometry. The structure of complex I is determined by single-crystal XRD (CIF file CCDC no. 2362544).

The reactions of [Zn(Piv)₂]_n and [Gd(Piv)₃]_n or Gd(NO₃)₃∙6H₂O with 2-hydroxypyridine (Hhp) or its 6-methyl derivative (Hmhp) afford heterometallic complexes [ZnGd(Рiv)₅(Hhp)₂]·0.5H₂O (I), [Zn₂Gd(Рiv)₆(Hhp)₂NO₃]∙2C₆H₆ (II), [Zn₃GdO(Рiv)₇(Hmhp)₂]∙MeCN (III), and [Zn₂Gd(Рiv)₆-(Hmhp)₂NO₃]∙0.5MeCN (IV), respectively. In the carboxylate metal cage of the synthesized complexes, the Hhp and Hmhp molecules in the form of 2-pyridone are coordinated by the metal atoms via the monodentate mode through the oxygen atoms. The introduction of Et₃N into the reaction with [Zn(Рiv)₂]_n, Gd(NO₃)₃∙6H₂O, and Hhp is found to result in the formation of compound [Zn₄Gd₂(OH)₂-(Рiv)₆(hp)₆(Hhp)₂] (V) in which the 2-hydroxypyridine anions perform the bridging function. The molecular structures of complexes I‒V are determined by XRD (CIF files CCDC nos. 2365419–2365423).