Synthetic studies in the 1,2-Dithiole series. II. Routes to 4-Methylamino-1,2-dithiole-3-thione

Abstract

4-Amino-1,2-dithiol-3-one has been converted via methylation of its N-tosyl derivative into the 4-methylamino-3-thione (Vb). Methylation of 4-benzamido-1,2- dithiole-3-thione with methyl iodide and a strong base gives 4-bis(methylthio)-methylene-2-phenyl-2-oxazoline-5-thione (VII). The N.M.R. and ultraviolet spectra of the oxazoline thione (VII) and of the corresponding oxazolinone (VIII) and thiazolinone (IX) are discussed in terms of their probable non-planarity. Some examples of long-range spin-spin coupling between protons of non-equivalent methyl groups in isopropylidene structures are reported.