Tetraphenylphosphonium Diiodobromide: Crystal and Molecular Structure

Complex formation in systems containing 3-carboxypropyltriphenylphosphonium or tetraphenylphosphonium bromide, molecular iodine, and chloroform solution was compared. The maximum number of iodine molecules coordinated by bromides in the solution was established by spectrophotometric method using a function of average iodine number and the stability constants of the complexes were determined. The diiodobromide [(C₆H₅)₄P]BrI₂ was studied by X-ray diffraction analysis. The ab initio calculations were performed for [Y(R)₄]I₃ (Y = N, P, As; R = CH₃, C₆H₅). The obtained experimental data and the correlations with the results of quantum-chemical calculations revealed that the tetraphenylphosphonium cation binds diiodobromide anions through the terminal halogen atoms with equal probability.     

Structure of 6,11-dichloro-9-dimethylthio-7,8-dicarba-nido-undecaborane [6,11-Cl2-9-SMe2-7,8-C2B9H9]

A technique is proposed for directed synthesis of 6,11-dichloro-9-dimethylthio-7,8-dicarba-nido-undecaborane [6,11-Cl₂-9-SMe₂-7,8-C₂B₉H₉]. Single-crystal X-ray diffraction is used to identify the molecular and crystal structure of the compound.     

Reactions of 2- and 4-pyrones with secondary phosphine chalcogenides: a facile synthesis of functional phosphorylated pyrones

The oxidative cross-coupling between 4-hydroxy-6-methyl-2-pyrone or 3-hydroxy-2-methyl-4-pyrone and secondary phosphine chalcogenides proceeds in CCl₄/Et₃N under mild conditions (20–52 °С, 0.75–10 h) through the hydroxyl group to give O-(6-methyl-2-oxo-2H-pyran-4-yl) diorganylphosphinochalcogenoates or O-(2-methyl-4-oxo-4H-pyran-3-yl) diorganylphosphinochalcogenoates, in high yields.     

New Data on the Isomorphism in Eudialyte-Group Minerals. ХI: Crystal Structure of a Potentially New Mineral—A Case of Complete Substitution of Fe2+ with $${\text{Na}}_{{{\text{2/3}}}}^{{\text{ + }}}{\text{Zr}}_{{{\text{1/3}}}}^{{{\text{4 + }}}}$$ in the Eudialyte-Type Structure

Crystallography Reports - The crystal structure and crystallochemical features of a Fe-deficient zirconium-rich analog of eudialyte from the Lovozero alkaline massif (Kola peninsula) have been...     

Structure and Properties of Anion-Radical Salt of 7,7,8,8-Tetracyanoquinodimethane with N-Methyl-2,2'-dipyridyl Cation

Crystallography Reports - Anion-radical salt of 7,7,8,8-tetracyanoquinodimethane with N-methyl-2,2'-dipyridyl cation is synthesized. Its composition is determined using electron spectroscopy...     

Reactions of 2-phenylpyrrole with bromobenzoylacetylene on metal oxides active surfaces

The solvent-free interaction of 2-phenylpyrrole with bromobenzoylacetylene (room temperature) upon their grinding with solid metal oxides (MgO, CaO, ZnO, BaO, Al₂O₃, TiO₂, ZrO₂) and salts (CaCO₃, ZrSiO₄) leads to either the cross-coupling product or the adduct of pyrrole addition to the riple bond of acetylene. The ethynylation is accompanied by the formation of intermediate and side products: E-2-(1-bromo-2-benzoylethenyl)-5-phenylpyrrole and 1,1-di(5-phenylpyrrol-2-yl)-2-benzoylethene. The activity of the metal oxides in the ethynylation reaction falls in the order (in the brackets, the content of 2-benzoylethynyl-5-phenylpyrrole in the reaction mixture is given): ZnO (81%), BaO (73%), Al₂O₃ (71%), MgO (69%), CaO (50%). The oxides, SiO₂, TiO₂, ZrO₂, and the salts, CaCO₃ and ZrSiO₄, are inactive in the ethynylation reaction affording only the intermediate adduct, with ZrO₂ the isolated yield of the bromoethenylpyrrole reaching 60%. ESR monitoring shows the reaction to start from one electron transfer from pyrrole to acetylene mediated by the oxide surface. The adduct is readily converted on Al₂O₃ to 2-(benzoylethynyl)-5-phenylpyrrole crystallized mostly as cis-rotamer (X-ray data).     

Structure and properties of bis{[2-(4-<Emphasis Type="Italic">tert</Emphasis>-butyl)phen]ethyl}phosphine sulfide

Previously unknown bis[2-(4-tert-butyl)phen]ethylphosphine sulfide is obtained with a high yield from 4-tert-butyl styrene, red phosphorus, and elemental sulfur. Using single crystal XRD, multinuclear NMR, IR, and UV spectroscopy, it is found that the phosphorus atom is four-coordinated in the bis[2-(4-tert-butyl)phen]ethylphosphine sulfide molecule (regardless of the phase state of the compound: crystal, solution). By the example of phosphorylation of bis[2-(4-tert-butyl)phen]ethylphosphine sulfide acetylene in the KOH-DMSO system it is shown that the reaction proceeds by double addition with the participation of phosphorus-centered nucleophiles.     

New fulvalenium salts of bis(dicarbollide) cobalt and iron: Synthesis, crystal structure and electrical conductivity

New radical cation salts (BEDT-TTF)₂[3,3′-Co(1,2-C₂B₉H₁₁)₂] (1), (BEDT-TTF)₂[8-I-3,3′-Co(1,2-C₂B₉H₁₀)(1′,2′-C₂B₉H₁₁)] (2), (BMDT-TTF)[3,3′-Co(1,2-C₂B₉H₁₁)₂] (3) and (TMTSF)₂[3,3′-Fe(1,2-C₂B₉H₁₁)₂] (4) were synthesized and their crystal structures and electrical conductivities were determined. Compound 4 is isostructural to the earlier reported Co analogue. All the radical cation salts synthesized are semiconductors.     

Spin-peierls transition in dimerized stacks of anion-radical salt (N-Me-2,5-di-Me-Pz)(TCNQ)2, (Pz is pyrazine)

An anion-radical salt (ARS) (N-Me-2,5-di-Me-Pz)(TCNQ)₂, where Pz is pyrazine, was synthesized and its crystal structure was resolved. X-ray diffraction experiments on single crystals were performed. Heat capacity was measured in the temperature range from 2 to 300 K. Magnetisation and magnetic susceptibility were measured in the temperature range from 2 to 300 K and the low-temperature part was measured in magnetic fields from 5 mT to 5 T. The experimental results were explained in terms of dimerized Heisenberg spin chain model. Numerical calculations were performed and compared with experimental data.     

Molecular conductors with 8,8′-diiodo cobalt bis(dicarbollide) anion

New molecular conductors on the base of 8,8′-diiodo cobalt bis(dicarbollide) anion (TTF)[8,8′-I₂-3,3′-Co(1,2-C₂B₉H₁₀)₂] (1), (BMDT-TTF)₄[8,8′-I₂-3,3′-Co(1,2-C₂B₉H₁₀)₂] (2) and (BEDT-TTF)₂[8,8′-I₂-3,3′-Co(1,2-C₂B₉H₁₀)₂] (3) were synthesized and their crystal structures and electrical conductivities were determined. All the radical cation salts prepared were found to be semiconductors. Some regularities in the crystal structures of the TTF-based radical cation salts with bis(dicarbollide) complexes of transition metals are discussed.