2,2,4-Trimethylhydroquinolines in the Bischler-Melau Reaction

8-R-1-Aryl-4,4,6-trimethyl-4H-pyrrolo[3,2,1-ij]quinolines have been synthesized by the Bischler-Melau reaction in the series of 6-R-2,2,4-trimethylhydroquinolines.     

CO Oxidation on Cu/MgO-SiO2 Sol-Gel Derived Catalysts

Sol-gel Cu//MgOSiO₂ catalysts were prepared gelling tetraethoxysilane (TEOS), magnesium ethoxide and copper acetylacetonate at pH 3 and pH 9. The catalysts shown specific surface areas ca. 500 m²/g and 140 m²/g for pH 9 and pH 3 preparations respectively. Si(OH) and Si(OH)₂ hydroxy groups were observed by MAS-RMN spectroscopy in both preparations. CO₂-TPD and NH₃-TPD desorption thermograms showed that acid and basic sites were formed on the catalysts surface. It has been found that the catalysts having the highest density of basic sites were the catalysts showing the highest activity for the CO oxidation. It is proposed that the catalytic activity depends of the relative Cu⁼¹/Cu⁼² stability given by the support acidity.     

New method for calculating the adsorption of noble gases on amorphous surfaces

A new approach to calculating the equilibrium characteristics of the adsorption of noble gases on the amorphous surfaces of adsorbents was developed and applied to the Ar−TiO₂(rutile) system. Intermolecular adsorbate-adsorbate interactions are taken into account for the nearest neighbors in the quasi-chemical approximation. The lattice energy parameters of all interactions of the model are determined from the Lennard-Jones potential (12-6). The formation of amorphous TiO₂(rutile) surface includes completion of the surface layers and partial removal of the surface oxygen ions. The quality of the amorphization procedure was confirmed by the experimentally measured heats and isotherms of adsorption of the system under study. Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 6, pp. 1109–1118, June, 1997.     

Hydrolysis and Condensation of Transition Metal Alkoxide: Experiments and Simulations

We present here an experimental and numerical study of the chemical and aggregative mechanisms for titanium alkoxide in a reverse micellar medium. NMR experiments were done to study the first step of the sol-gel process: hydrolysis of titanium isopropoxide. Light and X-ray scattering experiments were then conducted to characterize the clustering of aggregates and aggregation kinetics. Fractal dimension, measured by U.S.A.X.S., varies with the hydrolysis ratio and the hydration of the surfactant. This evolution was explained by polydispersity of the hydrolysis which depends on the surfactant concentration. This hypothesis was tested through a numerical simulation of irreversible aggregation using a chemically limited aggregation model. The hydrolyzed sites are distributed among the monomers by a random procedure governed by a polydispersity parameterp, varying from 0 to 1. The total number of hydrolyzed sites is governed by a parameterq belonging to the interval [0, 1]. Thep-q evolution of the fractal dimension coincides rather well with the experimental data in all the region of the two dimensional phase space.     

Reaction of vinyloxyalkylamines with mercaptoacetic acid

N-[2(3)-Hydroxyalkylj-4-thiazolidinones have been synthesized by the reaction of 2(3)-vinyloxyalkylamines with mercaptoacetic acid in 24–69 % yield. The structure of the compounds obtained was supported by (R and¹H NMR spectroscopic data.Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 3, pp. 677–679, March, 1996.     

Additive telluromolybdates. Structure and catalysis in oxidation

Additive telluromolybdates, MoO₃·2TeO₂ and M^IIO·TeO₂·MoO₃ (M^IITeMoO₆; M^II = Co, Mn, Zn), converted ethyl lactate selectively to pyruvate in a vaporphase fixedbed flow system at 250–300 °C. A synergy in activity was observed for binary TeO₂–MoO₃, and crystalline Te₂MoO₇ was suggested as the active species. The Rietveld analysis of powder XRD patterns of ternary CoTeMoO₆ revealed the layer structure quite different from that of the reference Te₂MoO₇, but tellurium was again located adjacent to molybdenum linked through lattice oxygen.     

Polyfluorinated hydrazones in organic synthesis

A preparative one-step method for the synthesis of 1,1,1,5,5,5-hexafluoro-4-trifluoromethylpentane-2,3-dione dihydrazone from perfluoro-4-methylpent-2-ene and hydrazine hydrate has been developed. Oxidation of this dihydrazone with bromine in water gives 3-diazo-1,1,1,5,5,5-hexafluoro-4-trifluoromethylpentane-2-one. The same product is obtained from 3-hydrazono-1,1,1,5,5,5-hexafluoro-4-trifluoromethylpentane-2-one under similar conditions.Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 11, pp. 2039–2041, November, 1994.This work was supported by the Russian Foundation for Basic Research (the project code 94-03-08548).     

Synthesis and some properties of planar 4-diphenylphosphino-1,3,2-dioxaborinanes

Fused 1,3,2-dioxaborinanes, derivatives of 4-diphenylphosphino- and 4-diphenylphosphoryl-4H-1, 3-dioxa-2-boraphenanthrenes, and their complexes with amines have been synthesized. According to X-ray diffraction data, the complex of 2-phenyl-4-diphenylphosphoryl-4H-1, 3-dioxa-2-boraphenanthrene with butylamine exists as a dimer due to the formation of intermolecular hydrogen bonds.Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 9, pp. 1649–1655, September, 1994.The present work was financially supported by the International Science Foundation (grant No. RHBOOO).     

2,6—二氯—4—溴偶氮胂光度法测定微量铀（Ⅵ）

本报道用了２，６－二氯－４－溴偶氮胂作显色剂测定微量铀（Ⅵ）的光度法。在Ｈ２ＳＯ４介质中，铀（Ⅵ与）２，６－二氯－４－溴偶氮胂形成１：２络合物，其λｍａｘ＝６４０ｎｍ；表观摩尔吸光系数为１．１×１０＾５Ｌ．ｍｏｌ＾－＾１．ｃｍ＾－＾１；铀的浓度在０．０－２２．０μｇ／ｍｌ内符合比耳定律。方法具有灵敏度高，选择性好，操作方便等特点并已用于废水及矿样中微量铀（Ⅵ）的测定。     

Reaction of 2-diethylamino-3-diethylaminomethyl-1,3,2-benzoxazaphospholine with hydroxyl-containing compounds

The reaction of 2-diethylamino-3-diethylaminomethyl-1,3,2-benzoxazaphospholine with functionally substituted alcohols and phenols occurs with the cleavage of exocyclic P-N bond followed by N→P migration of the diethylaminomethyl group and formation of imidophosphonate dimers. A similar reaction with polyhydroxy compounds (diethylene glycol, glycerol) results in symmetrical and asymmetrical spirophosphoranes. Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 10, pp. 1781–1784, October, 1993.