Nitroso derivatives of 1,3-dithiol-2-ylidene stabilised by intramolecular oxygen ⋯ sulfur interactions: synthesis and X-ray crystal structures.

Abstract

A series of 2-(nitrosomethylene)-1,3-dithiole derivatives 3 have been synthesised, and X-ray crystal structures of compounds 3g, 3h and 3I have been obtained. The coplanarity of the dithiole ring and the nitroso group in all three compounds favours π-conjugation, and short intramolecular oxygen ⋯ sulfur contacts (ca. 2.4 Å) occur between the nitrosyl oxygen and a sulfur atom of the dithiole ring; these structural features explain the stability and unreactivity of the series of compounds 3.