SYNTHESIS, REACTIONS AND SPECTRAL PROPERTIES OF 3-CHLORO-2,6DIARYL-4H-THIOPYRAN-4-ONES. SYNTHESIS OF SOME NEW 3-CHLORO-SPIROTHIOPYRAN DERIVATIVES

Abstract

3-Chloro-2-phenyl-6-p-tolyl and 3-chloro-2,6-di-p-tolyl-4H-thiopyran-4-ones have been synthesized in moderate yieldes from the reaction of 3-chloro-tetrahydrothiopyran-4-ones with phosphorus pentachloride. Their thiones, oximes, and hydrazones have been also prepared. Treatment of thiones with malononitrile gave the corresponding 3-chloro-4-thiopyrylidenemalononitriles which gave 3-chloro-spirothiopyran derivatives of pyrazole, isoxazole, 1,3-thiazines when treated with hydrazine hydrate, hydroxylamine hydrochloride, thiourea and thiosemicarbazide, respectively. While treatment of 3-chloro-thiopyrylidene-malononitriles with acetylacetone gave the corresponding 3-chloro-spirothiopyran derivatives of pyran.

Keywords:

• 3-Chlorothiopyrones
• 3-chlorothiopyrylidenemalononitriles
• NMR spectra
• mass spectra
• 3-chlorospirothiopyranes

I would like to thank Dr. Bassam El Ali and King Fahd University of Petroleum and Minerals, Saudi Arabia, Chemistry Department for helping with the spectra and elemental analysis of this work.