Structural Aspects of 5-methylthio-1-oxa-6,6a δIV-dithia-2-azapentalenes

Alkylation of 5-[1-hydroxyiminoalkyl]-1,2-dithiole-3-thiones using methyl iodide in the presence of sodium hydroxide gives derivatives which may be considered as being 5-methylthio-1-oxa-6,6a δIV-dithia-2-azapentalenes with quantitative yields. The structure of oxadithiazapentalene attributed to the alkylation products is founded on X-ray analysis and NMR and IR data.