3,5-DIALKYLTETRAHYDRO-4<i>H</i>-THIOPYRAN-4-ONES UNDER THE CONDITIONS OF MANNICH REACTION

Abstract

Thiomethylation of pentan-3-one, 5-methylhexan-3-one, and heptan-4-one with a mixture of formaldehyde and sodium sulfide gave the respective 3,5-dialkyltetrahydro-4H-thiopyran-4-ones, while 3,5-dihydroxymethyl- or 3,5-dialkyl-5-hydroxymethyltetrahydro-4H-thiopyran-4-ols were formed in the presence of primary amines. The oxidation of 3,5-dimethyltetrahydro-4H-thiopyran-4-one with an equivalent amount of hydrogen peroxide in tetrahydrofuran and chloroform led to the sulfoxide and sulfone, respectively, while aminomethylation with a mixture of formaldehyde and methylamine, hexylamine, monoethanolamine, or hydrochlorides of methyl, ethyl, and 2-propyl esters of aminoacetic acid at рH 7–8 produced the respective 1,5-dimethyl-3-thia-7-azabicyclo[3.3.1]nonanes. An equilibrium between the chair and boat conformations in the thiopyranone ring was found in CDCl₃ solutions of 7-(2-hydroxyethyl)-1,5-dimethyl-3-thia-7-azabicyclo[3.3.1]nonan-9-one at 50°С and DMSO-d₆ solutions of 1,5,7-trimethyl-3-thia-7-azabicyclo[3.3.1]nonan-9-one monoperchlorate at 20°С.

How to Cite
Baeva, L. A.; Biktasheva, L. F.; Fatykhov, A. A.; Lyapina, N. K. Chem. Heterocycl. Compd. 2015, 51, 969. [Khim. Geterotsikl. Soedin. 2015, 51, 969.]

For this article in the English edition see DOI 10.1007/s10593-016-1806-x