Acetic Acid → HCID 66906147, compound

Participants

Reaction Conditions

Reaction Steps

A 2-L reactor equipped with overhead stirrer and thermocouple was charged with 150 g (0.672 mol) of 2-[(ethoxycarbonyl)amino]-3-methylbenzoic acid (ca. 98% purity) and acetic acid (500 g). The resulting slurry was heated to 35-40° C. to give a solution, which was cooled to 30° C., and then hydrochloric acid (37%, 150 g, 1.5 mol, 2.2 eq) was added. The mixture was maintained at 30° C. while aqueous hydrogen peroxide (30%, 96 g, 0.85 mol, 1.25 eq) was added over about 1 h. The mixture was then warmed to 35° C. and held at that temperature for about 1 h. About 600 mL of water was metered in over about 30 minutes, while maintaining the temperature at 30-35° C. The mixture was cooled to 10° C., and the product was collected by filtration, and the wet cake was washed with water (3×100 mL); the third wash tested negative with KI-starch paper. The wet cake was dried to constant weight in a vacuum oven at 50° C. The crude yield was about 150 g (about 84% based on an estimated purity of 2-[(ethoxycarbonyl)amino]-3-methylbenzoic acid of 98% and estimated product purity of 95%). A portion of the crude product was first recrystallized from toluene and then recrystallized from aqueous methanol to give an analytical sample melting at 124-126° C.

Provenance & Evidence