THE SYNTHESIS AND PROPERTIES OF 6-TRIFLUOROMETHYL-SUBSTITUTED THIOPYRANO[3,4-<i>d</i>]ISOXAZOLE DERIVATIVES

Abstract

The first representatives of the novel 4,7а-dihydro-3аН-thiopyrano[3,4-d]isoxazole heterocyclic system, containing an ester, carboxyl, or hydroxymethyl group at position 3 and a trifluoromethyl group at position 6 were obtained by [3+2] cycloaddition reaction of ethyl cyanocarboxylate N-oxide and 6-trifluoromethyl-2Н-thiopyran, followed by further transformations of the ethyl 6-trifluoromethyl-4,7а-dihydro-3аН-thiopyrano[3,4-d]isoxazole-3-carboxylate intermediate. The cleavage of the isoxazoline ring of the obtained compounds led to the formation of 6-trifluoromethyl-2Н-thiopyran derivatives with nitrile or carbonyl-containing functionality at position 3. Transformations of the thiopyran moiety in 4,7а-dihydro-3аН-thiopyrano[3,4-d]isoxazole were studied for the case of Pummerer reaction product with oxidized sulfur atom, ethyl 6-trifluoromethyl-4,7а-dihydro-3аН-thiopyrano[3,4-d]isoxazole-3-carboxylate 5-oxide, which was converted to ethyl 6-trifluoromethyl-4Н-thiopyrano[3,4-d]isoxazole-3-carboxylate.

How to Cite
Siryi, S. A.; Timoshenko, V. M.; Vlasenko, Yu. G.; Rusanov, E. B.; Shermolovich, Yu. G. Chem. Heterocycl. Compd. 2015, 51, 630. [Khim. Geterotsikl. Soedin. 2015, 51, 630.]

For this article in the English edition see DOI 10.1007/s10593-015-1750-1