Lawesson's reagent in toluene

β-mercaptopropionic acid methyl ester; sodium methylate 1) DMF, 1 to 1.5 h heating on a steam bath, 2) MeOH, 1 h, reflux; Yield given. Multistep reaction;

1: 72 percent / H2SO4, NaNO2 / H2O / 1 h / 70 °C 2: 67 percent / Lawesson's reagent / toluene View Scheme