反应详情

5-m-Tolyl-1,3,4-oxathiazol-2-one (19.32 g, 0.1 mol) and dimethyl acetylenedicarboxylate (28.42 g, 0.2 mol) were heated at reflux in 60 ml of chlorobenzene as given above. After the initial crystallization from cold methanol, three recrystallizations from diethyl ether/petroleum ether gave 15.18 g (0.0522 mol, 52.2%) of white solid, m.p. 53°-54.5°.

1. customAfter the initial crystallization
2. customfrom cold methanol, three recrystallizations from diethyl ether/petroleum ether