1,3,5-Trisubstituted 1,3,5-triazinane-2-thiones from 1,3,5-trisubstituted 1,3,5-triazinanes and organic isothiocyanates

Abstract

1,3,5-Trisubstituted 1,3,5-triazinane-2-thiones 8 were obtained in high yields by the uncatalysed reaction between 1,3,5-triaryl or -trialkyl 1,3,5-triazinanes 1 with aryl or alkyl isothiocyanates 4 at 130 °C. Only the reaction of 1,3,5-triaryl-1,3,5-triazinanes 1 with alkyl isothiocyanates 4 failed. Although no other type of cyclization was detected, the systems in which the substituent in 4 was different from that in 1 exhibited more or less extensive random redistribution of the substituents, according to a retrocyclization–recyclization mechanism. X-Ray crystallographic data were obtained for two derivatives 8f and 8m. ¹H and ¹³C NMR data, as well as electron impact fragmentations, were collected and are discussed.