Hydrochloric Acid → 4-Fluoro-alpha-[(phenylmethyl)amino]benzeneacetic acid methyl ester hydrochloride

Participants

Reaction Conditions

Reaction Steps

4-Fluoro-α-[(phenylmethyl)amino]benzeneacetic acid (12.2 kg, 47.1 moles) was slurried in methanol (37 L), then hydrogen chloride gas was passed over the mixture. The resulting slurry was stirred at 35-45° C. for 3 hours, then concentrated to 30-35 L by distillation. Methyl-t-butyl ether (20 L) was added and the batch was seeded with 4-Fluoro-α-[(phenylmethyl)amino]benzeneacetic acid methyl ester hydrochloride. Upon development of the seed-bed, methyl-t-butyl ether (20 L) was added. The slurry was aged for 1 hour, then filtered. The filter cake was washed with methyl-t-butyl ether:methanol (95:5, 8.0 L), then dried under vacuum at 30° C. to give 12.2 kg (84% yield) of 4-fluoro-α-[(phenylmethyl)amino]-benzeneacetic acid methyl ester hydrochloride.

Provenance & Evidence