Treatment of methyl N-methylthionocarbamate (2a) with a catalytic amount of iodine or conc. H2SO4 results in the unexpected formation of the isomer, methyl N-methylthiolcarbamate (3a) in 90% yield. This has subsequently been transformed into methyl N-methylcarbamate (4a), by sodium methoxide. A curious transformation of methyl N-methyldithiocarbamate (1a) to (4a) on prolonged treatment with sodium methoxide is also discussed.
