Synthesis of the first stable carborane containing simple enol

A carborane-containing stable simple enol — 1-2-isopropyl-o-carboran-I-yl)-1-phenyl2-mesityl-2-lrydroxyctlrylcne — has been synthesized. This enol does not isomerize to the starting ketone or keto-enol mixture even after prolonged heating in benzene in the presence of CF₃COOH.Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 6, pp. 1561–1563, June, 1996.     

Synthesis and reactions of heterocyclic compounds

5-Azido-2-methylbenzthiazole, 6-azido-1, 2-dimethyl-, and 5-azido-2-methyl-1-phenylbenzimidazoles were prepared. By the reactions of these azides with alkyl halides the quaternary slats based on the cyanine dyes were obtained.     

Synthesis of o- and m-Carborane-substituted Porphyrins of the Natural Type

Basing on protoporphyrin IX, its monobenzyl ester, deuteroporphyrin IX, 9-hydroxymethyl-m- and 9-hydroxymethyl-p-carboranes, mono- and dicarborane-containing porphyrins were prepared.     

Synthesis of mono-, di-, tri-, and tetraethyl-o-carboranes by electrophilic alkylation ofo-carborane with ethyl bromide in the presence of AICl3 and their transformations

Optimal conditions for the preparation of 9-ethyl-, 9,12-diethyl, 8,9,12-triethyl-, and 8,9,10,12-tetraethyl-o-carboranes under the action of EtBr on o-carborane in the presence of AICl₃ were determined. The behavior of these o-carborane derivatives towards electrophilic and nucleophilic reagents was studied. The presence of four ethyl groups in positions 8, 9, 10, and 12 of the carborane polyhedron increases the electron density on the boron atoms in positions 4, 5, 7, and II to the point where they are able to enter into reactions of electrophilic substitution, and in positions 3 and 6 to the point that they become resistant to the action of nucleophilic reagents. Reactions of 1,2-dilithium-8,9,10,12-tetraethyl-o-carborane with various electrophilic reagents were studied.Translated fromIzvestiya Akademii Nauk, Seriya Khimicheskaya, No. 11, pp 2755–2763, November, 1996.     

Synthesis and reactions of heterocyclic azide derivatives. 6. Reactions of benzothiazole azides with 1,3-diketones and iotisch complexes

Cycloaddition of 5- and 6-azido-2-methylbenzothiazoles to magnesiumbromoacetylenes and 1,3-diketones leads to the formation of 2-methyl-5(6)-(1,2,3-triazol-1-yl)benzothiazoles. Reaction with benzoylacetone, for instance, results in the formation of two isomeric 4-acyl-1,2,3-triazoles, which differ in the position of the methyl and phenyl substituent radicals.For Communication 5, see [1].Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 8, pp. 1120–1123, August, 1990.     

Higher order symmetrizer and application to an unusual transport equation

We study a class of stationary transport equation with nonlocal low-order tems We obtain the existence and uniqueness of a solution in sobolev spaces