1,3,5-TRISUBSTITUTED 1,3,5-TRIAZINANE-2-THIONES FROM 1,3,5-TRISUBSTITUTED 1,3,5-TRIAZINANES AND ORGANIC ISOTHIOCYANATES

1,3,5-Trisubstituted 1,3,5-triazinane-2-thiones 8 were obtained in hig h yields by the uncatalysed reaction between 1,3,5-triaryl or -trialky l 1,3,5-triazinanes 1 with aryl or alkyl isothiocyanates 4 at 130 degr ees C. Only the reaction of 1,3,5-triaryl-1,3,5-triazinanes 1 with alk yl isothiocyanates 4 failed. Although no other type of cyclization was detected, the systems in which the substituent in 4 was different fro m that in 1 exhibited more or less extensive random redistribution of the substituents, according to a retrocyclization-recyclization mechan ism. X-Ray crystallographic data were obtained for two derivatives 8f and 8m. H-1 and C-13 NMR data, as well as electron impact fragmentatio ns, were collected and are discussed.