Cyclic sulphur-nitrogen compounds and phosphorus reagents: Part XIII¹-Reactions of cyclic sulphur-nitrogen chlorides with Ph₃P-influences of tertiary base, Et₃N and the ring size of the cyclothiazyl chloride on the product formation

Abstract

961-966Similar to the reactions with S4N3Cl and S3N3Cl3,triphenylphosphine reacts with five-membered cyclic sulphur-nitrogen chlorides namely, S3N2Cl and S3N2Cl2 to give triphenylphosphiniminium chloride, Ph3P=NHCl- as the major product. Maximum yield (ca. 90%) is obtained when triphenylphosphine is reacted with S3N2Cl in acetonitrile at room temperature in 2:1 molar ratio. Analogous reactions performed in presence of triethylamine afford two cyclothiazene products containing phosphinimino substituent. The ring size of the S-N chloride seems to determine the nature of phosphiniminocyclothiazenes formed. A rationalization of the results obtained has been attempted