N. A. Zhukovskaya

Synthesis of functionally substituted isoxazole and isothiazole derivatives

Acylation of benzene and toluene with 5-phenyl- and 5-(p-tolyl)isoxazole-3-carbonyl chlorides gave 5-phenyl(or p-tolyl)isoxazol-3-yl phenyl(or p-tolyl)ketones which were reduced to the corresponding alcohols with sodium tetrahydridoborate in propan-2-ol. Selective reduction of the carboxy group in 4,5-dichloroisothiazole-3-carboxylic acid was achieved by the action of BH3, and the aldehyde group in 4-formyl-2-methoxyphenyl 5-arylisoxazole-3-carboxylates and 4,5-dichloroisothiazole-3-carboxylates was reduced to hydroxymethyl group with sodium triacetoxyhydridoborate in benzene. Acylation of the resulting hydroxymethyl derivatives with 5-arylisoxazole- and 4,5-dichloroisothiazole-3-carbonyl chlorides afforded the corresponding esters containing two azole fragments in their molecules.

Preparative synthesis of 4-hydroxy(alkyloyloxy, aryloyloxy)-3-methoxy(ethoxy)phenylmethylene(4-carboxyphenyl)amines

By reactions of vanillin, vanillal, and their esters with 4-aminobenzoic acid in methanol formerly unknown E-isomers of azomethines (Schiff’s bases) were prepared.

Synthesis of hydroxybenzaldehyde derivatives containing an isoxazole heteroring

Abstract5-Phenyl(p-tolyl)isoxazole-3-carboxylic acids were synthesized starting from 3-hydroxyiminomethyl-5-phenyl(p-tolyl)isoxazoles, and their reactions with p-hydroxybenzaldehyde, vanillin, isovanillin, o-vanillin, and ethyl vanillin gave the corresponding esters. The latter were brought into condensation with aromatic amines to obtain Schiff bases which were reduced to amines.

Esters of Vanillin and Vanillal Oximes

Vanillin and vanillal oximes 2a and 2b were used to prepare the corresponding esters 3a-k, 4a-k, and 5a-c by reaction with acyl chlorides in the presence of pyridine.

Esters of isoxazole- and isothiazolecarboxylic acids and oximes of β-isatin, isoxazole- and ferrocene-containing ketones and carborane alcohols

Oximes of β-isatin, isoxazole- and ferrocene-containing ketones, o- and m-carborane alcohols react with isoxazol- and isothiazolecarboxylic acid chlorides in the presence of triethylamine to afford the corresponding esters.

Synthesis and structure—aroma correlation of citral oxime esters

Citral (3,7-dimethyl-2,6-octadienal, 1) occurs in lemongrass, cubeb, citrus, and other essential oils as a mixture of the Eand Z-isomers in a 7:3 ratio. This aldehyde ( 1) has a strong lemon odor [1] and is used widely in many perfume compositions. The goal of our work was to develop preparative synthetic methods of citral oxime esters through the reaction of citral oxime (2) with alkylcarboxylic acid anhydrides or alkyland arylcarboxylic acid chlorides in the presence of pyridine. The synthesis was performed at 20-23°C for 24-36 h by simply mixing the appropriate reagents and pro ceeded without using cooling and prolonged stirring. Citral oxime esters 3-22 were prepared in 74-88% yield.

Synthesis of esters of metallocene alcohols and 4,5-dichloroisothiazol-3-carboxylic and 5-arylisoxazole-3-carboxylic acids

Acylation of alkyl- and 1,1′-dialkylferrocene alcohols and diols as well as (3,4,4-trichlorobut-3-ene-1-ol-1-yl)-4,5-cymantrene with dichloroisothiazole- and 5-arylisoxazole-3-carbonyl chlorides has afforded esters containing 1,2-azoles fragments. Some of the obtained compounds have exhibited potentiating action in the binary mixtures with insecticides.

Synthesis of 2-R-1,3-dioxanes, derivatives of functionally substituted aldehydes of vanillin series

By the condensation of substituted aldehydes of vanillin series with 1,3-propanediol in boiling benzene in the presence of sulfo cation exchanger FIBAN K-1 as catalyst functionally 2-R-substituted 1,3-dioxanes were synthesized.

Synthesis of 1,1′-diacetylferrocene dioxime esters

Abstract1,1′-Diacetylferrocene dioxime was synthesized by the reaction of 1,1′-diacetylferrocene with hydroxylamine. The dioxime reacts readily with carboxylic acids chlorides in the presence of pyridine with the formation of 1,1′-diacetylferrocene dioxime esters.

Preparative synthesis of veratraldehyde and citral oxime esters

Procedures were developed for preparing veratraldehyde, oximes of veratraldehyde and citral, and esters of these oximes, which are readily accessible fragrance compounds that can be synthesized from commercially available raw materials.