The Reaction of 2,4,6-Triphenyl-1,3,5-thiadiazin-1-ium Salt with Active Methylene Compounds

• Published in: Bulletin of the Chemical Society of Japan Vol. 55; no. 7; pp. 2158 - 2160
• Main Author: Shibuya, Isao
• Format: Journal Article
• Language: English
• Published: Tokyo The Chemical Society of Japan 01.07.1982; Chemical Society of Japan
• ISSN: 0009-2673; 1348-0634
• DOI: 10.1246/bcsj.55.2158

The reaction of 2,4,6-triphenyl-1,3,5-thiadiazin-1-ium tetrafluoroborate with several active methylene compounds was studied. Nitromethane and nitroethane gave 2H-1,3,5-thiadiazines. The compounds possessing a benzoyl group reacted with this salt to give 5-substituted 2,4,6-triphenylpyrimidines, while those possessing a carbamoyl group afforded 5-substituted 4-hydroxy-2,6-diphenylpyrimidines or 4(3H)-pyrimidinone. On the other hand, malononitrile and ethyl cyanoacetate gave 5-substituted 4-mercapto-2,6-diphenylpyrimidines, with the liberation of benzonitrile. It was thus found that 2,4,6-triphenyl-1,3,5-thiadiazin-1-ium tetrafluoroborate reacts with active methylene compounds in fashions similar to that of 2,4,6-triphenyl-1,3-thiazin-1-ium salt.