Azo coupling of 5-substituted furan-2(3H)-ones and 1H-pyrrol-2(3H)-ones with arene(hetarene)diazonium salts

5-Substituted furan-2(3H)-ones and 1-phenyl-1H-pyrrol-2(3H)-ones reacted with diazonium salts derived from substituted anilines and 1H-1,2,4-triazol-5-amine to give azo coupling products at the methylene group in the heteroring. The products were found to exist as hydrazone tautomers.     

Tetra-p-Tolylantimony 4-Methylbenzenesulfonate: Synthesis and Structure

Tetra-p-tolylantimony 4-methylbenzenesulfonate (I) was synthesized via the reaction of tri-p-tolylbismuth bis(4-methylbenzenesulfonate) with penta-p-tolylantimony in toluene. According to the X-ray diffraction data, the antimony atoms of two individual molecules of I have a distorted trigonal bipyramidal coordination with the axial 4-methylbenzenesulfonate ligand and three equatorial tolyl ligands, one of which contains four carbon atoms disordered over two sites with the occupancy factors 0.7 and 0.3.     

Synthesis and Crystal Structure of Tetraphenylbismuth Benzenesulfonate Hydrate and Tetraphenylbismuth 3,4-Dimethylbenzenesulfonate

The reaction of pentaphenylbismuth with SO₃ or with triphenylbismuth bis(benzenesulfonate) in benzene gave tetraphenylbismuth benzenesulfonate monohydrate (I). Tetraphenylbismuth 3,4-dimethylbenzenesulfonate (II) was prepared from pentaphenylbismuth and triphenylbismuth bis(3,4-dimethylbenzenesulfonate) in benzene. The structures of compounds I and II were established by X-ray diffraction. The Bi atoms have a distorted trigonal-bipyramidal coordination where the arenesulfonate group occupies an axial position. The Bi–C(average) and Bi–O distances in molecules I and II are 2.204(2), 2.695(2) Å and 2.205(2), 2.728(2) Å, respectively.     

Synthesis and Structure of Tetraphenylstibonium and Tetraphenylphosphonium Hydrogen Sulfates

Reactions of pentaphenylantimony and pentaphenylphosphorane with sulfuric acid yielded tetraphenylstibonium and tetraphenylphosphonium hydrogen sulfates, respectively; their crystal and molecular structure was determined.     

Influence of the molecular structure on the quenching of triplet states of porphyrins by molecular oxygen

Translated from Zhurnal Prikladnoi Spektroskopii, Vol. 50, No. 4, pp. 618–623, April, 1989.     

Concentrational quenching of triplet state in water-soluble chlorophyll-like molecules

Translated from Zhurnal Prikladnoi Spektroskopii, Vol. 50, No. 6, pp. 961–966, June, 1989.     

Pentafluoroperbenzoic acid as the efficient reagent for Baeyer–Villiger oxidation of cyclic ketones

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Octacarbamoylated and octathiocarbamoylated resorcinarenes: transformations and acceptor properties

A series of octa(thio)carbamoylated resorcinarenes was synthesized by the reactions of rccc-resorcinarenes with N,N-dimethylcarbamoyl and N,N-dimethylthiocarbamoyl chlorides in the presence of alkali carbonates. The derivatives with thiocarbamoyl groups were transformed into octa(carbamoylthio)resorcinarenes by the thione—thiol rearrangement. In a homogeneous medium octacarbamoylated resorcinarenes demonstrated high acceptor properties and selectivity to cesium cations but manifested low extraction ability towards alkali metal cations from the aqueous phase to organic one because of the formation of stable films at the interface. Resorcinarenes with thiocarbamoyl and carbamoylthio groups are capable of extracting lanthanides (Nd³⁺, Yb³⁺) from aqueous media and are selective to Nd³⁺ cations.