Infrared study of 1,3-thiazolidin(e)-2-one, -2-thione, and -2-selone and their 1-oxa-analogues

Abstract

1,3-Thiazolidin(e)-2-one, -2-thione, and -2-selone and their 1-oxa-analogues have been studied by i.r. spectroscopy over the range 4000-200 cm^–1. Spectroscopic evidence shows that in each series the zwitterionic form increases on passing from oxygen to selenium. The ν(CS) and ν(CSe) values for 1,3-thiazolidine-2-thione and -2-selone are tentatively located at 1 085 and 968 cm^–1 respectively. In 1,3-oxazoidine-2-thione ν(CS) is assigned to the medium intensity band at 1 110 cm^–1. Assignments are also made for ν(C–S) and ν(C–O) in the ring and for the out-of-plane and in-plane CS and CSe deformations.