Carbon Dioxide → HCID 11033155, compound

Participants

Reaction Steps

A solution of 412.2 g (2.3 mol) of 5-phenyl-1,3,4-oxathiazol-2-one, 662.7 g (4.66 mol) of dimethyl acetylenedicarboxylate, and 1 l. of chlorobenzene was heated at 135° for 6.5 hours, at which time CO2 evolution became very slow. Infrared and gas chromatography assays also indicated that the reaction was complete. The reaction mixture was concentrated under vacuum to 0.2 mm and 90°. The 680 g of pot residue was crystallized from about 700 ml of methanol to give 393 g of solid dimethyl 3-phenyl-4,5-isothiazoledicarboxylate, m.p. 70°-71.5°. An additional 69.9 g of solid, m.p. 70°-72°, was obtained from the filtrate. The total of 462.9 g amounted to a 72.7% yield.

Provenance & Evidence