Reaction of Diethyl Chloroethynylphosphonate with 3-Amino-1,2,4-triazoles

Russian Journal of General Chemistry - A series of new 6-phosphonylated 1H-imidazo[2,1-c][1,2,4]triazoles was synthesized by the reaction of diethyl chloroethynylphosphonate with 2-substituted...     

Refinement of the crystal structures of biomimetic weddellites produced by microscopic fungus Aspergillus niger

The single-crystal structures of four biomimetic weddellites CaC₂O₄ · (2 + x)H₂O with different contents of zeolitic water (x = 0.10–0.24 formula units) produced by the microscopic fungus Aspergillus niger were refined from X-ray diffraction data (R = 0.029–0.038). The effect of zeolitic water content on the structural stability of weddellite was analyzed. The parameter a was shown to increase with increasing x due to the increase in the distance between water molecules along this direction. The water content and structural parameters of the synthesized weddellites are similar to those of weddellites from biofilms and kidney stones.     

Luminescent heterometallic gold-copper alkynyl complexes stabilized by tridentate phosphine

The reactions between trinuclear gold complex tppmAu(3)Cl(3) (tppm = tris(diphenylphosphino)methane), arylacetylenes HC(2)C(6)H(4)X and Cu(+) under basic conditions result in formation of the heterometallic complexes [tppm(AuC(2)C(6)H(4)X)(3)Cu](+), X = H (1), COOMe (2), CN (3), OMe (4), NH(2) (5). These compounds belong to one structural motif and consist of the heterometallic {(AuC(2)C(6)H(4)X)(3)Cu} core stabilized by the tridentate phosphine. Compounds 1-5 were characterized by polynuclear NMR and IR spectroscopy, ESI-MS and single-crystal X-ray analysis. Luminescence properties of these complexes have been studied and revealed a substantial red shift of the emission maxima with the increase in the electron donicity of the alkynyl ligands substituents in the 550-680 nm range. The theoretical calculations of the electronic structures showed that variations of the substituents on the alkynyl ligands display very little effect on the molecular structural parameters but show appreciable influence on the orbital energies and luminescence characteristics of the compounds under study.     

Tiettaite K4Na12Fe3+Si16O41(OH)4 ⋅ 2H2O: A Mineral with a Novel Type of Microporous Heteropolyhedral Framework

Crystallography Reports - Microporous silicate tiettaite from the Khibiny alkaline massif (Kola Peninsula, Russia) has been studied using X-ray diffraction analysis, electron probe microanalysis,...     

Phosphorylated 2-Chloroethynes in the Reactions with Malonic Acid Derivatives: Azirine or Oxazole?

Russian Journal of General Chemistry - The reactions of (2-chloroethynyl)diphenylphosphine oxide with diethyl 2-aminomalonate and of dimethyl (2-chloroethynyl)phosphonate with...     

Synthesis and structure of alkyl 2-arylsulfanyl-3-nitroacrylates

Alkyl 2-arylsulfanyl-3-nitroacrylates were synthesized by the conjugate Michael addition of thiophenols to alkyl 3-bromo-3-nitroacrylates followed by elimination of HBr on treatment with Et₃N. When treated with 4-chlorothiophenol in the presence of Et₃N, alkyl 2-[(4-chlorophenyl) sulfanyl]-3-nitroacrylates can be transformed into alkyl 2,3-bis[(4-chlorophenyl)sulfanyl]- acrylates. The structures of the synthesized compounds were characterized by IR, UV, ¹H and ¹³C{¹H} NMR spectroscopy using ¹H–¹³C HMQC, ¹H–¹³C, and ¹H–¹⁵N HMBC techniques. Methyl 2-[(4-methylphenyl)sulfanyl]-3-nitroacrylate exists as the Z-isomer, as confirmed by X-ray diffraction.     

Synthesis of sulfolanopyranochromenones by the reaction of 2-benzylidene-3-methyl-4-nitro-2,5-dihydrothiophene 1,1-dioxides with 4-hydroxycoumarin

Chemistry of Heterocyclic Compounds - A number of tetracyclic compounds with annulated nitrosulfolane and pyranochromenone rings were synthesized by reacting...     

Chemically induced symmetry breaking in the crystal structure of guanidinium uranyl sulfate

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