S. A. Vasil'eva

Reaction of 4-methyl-3,4-epoxytetrahydropyran with ?-amino acids

Depending on the conditions, α-amino acids react with 4-methyl-3,4-epoxytetrahydropyran at the amin or carboxy group to give products of opening of the oxirane ring in conformity with the Krasusskii rule.

Reactions of epoxides of the pyran series involving ring expansion. Reaction of 4-methyl-3,4-epoxytetrahydropyran with potassium thiocyanate

The reaction of 4-methyl-3,4-epoxytetrahydropyran with potassium thiocyanate occurs with expansion of the oxirane ring and leads to 6-methyl-8-amino-3,7-dioxa-9-thiabicyclo[4,3,0]nonane, the formation of which has been proven by the fact that products of its acylation by acid chlorides of 2-R-cinchonic acids are obtained, and also by the formation of Mannich bases when it is treated with formaldehyde and secondary amines.

Reaction of 4-methyl-3,4-epoxytetrahydropyran with nucleophiles

Reaction of 4-methyl-3,4-epoxytetrahydropyran with phenols, thiols, thiocyanic acid and benzoic acid, thiourea, and with sodium sulfite and thiosulfate occurs with opening of the epoxide ring. Using IR spectroscopy it was shown that the products occur via trans-diaxial opening of the oxide ring at the least-substituted carbon atom.

Synthesis of 3-methylglutaric acid

Abstract4-Methyltetrahydropyran has been synthesized by catalytic hydrogenation of a mixture of the isomeric 4-methyl-5,6-dihydro- and 4-methylenetetrahydropyrans. Oxidative degradation then led to 3-methylglutaric acid.

Epoxidation of 2-aryl-4-methyl-3,6-dihydropyrans and reaction of the products with piperidine

Abstract2-Aryl-4-methyl-4,5-epoxytetrahydropyrans, which react with piperidine regioselectively with trans-diaxial cleavage of the oxide ring at the least substituted carbon atom, were synthesized by the reaction of 2-aryl-4-methyl-3,6-dihydropyrans with peracids.

Reaction of 2-imino-3-aryl-4-oxothiazolidines with phenyl isothiocyanate

Abstract2-Phenylthiocarbamoylimino-3-aryl-4-oxothiazolidines, which are hydrolyzed at the C=N and N3=C4 bonds of the thiazolidine ring to give 3-arylthiazolidine-2,4-diones, N-phenylthiocarbamoylarylpseudothiohydantoic acids, and 3-phenylthiocarbamoylthiazolidine-2,4-dione, were synthesized by reaction of 2-imino-3-aryl-4-oxothiazolidines with phenyl isothiocyanate.

Aminomethylation of some 4-thiazolidinones

Abstract2-Arylaminomethylimino-3-aryl-4-oxothiazolidines were obtained by the Mannich reaction. The structure of the isolated products was confirmed by acid hydrolysis, the formation of monoacetyl derivatives, and the IR spectra.