Acetic Anhydride → HCID 86744579, compound

Participants

Reaction Steps

To a stirred solution of 2.72 parts of trans-4-[(2-amino-6-methoxybenzoyl)amino]-3-hydroxy-N,N,γ-trimethyl-α,α-diphenyl-1-piperidinebutanamide in 20 parts of acetic acid were added 0.56 parts of acetic acid anhydride. After stirring overnight at room temperature, the reaction mixture was evaporated and the residue was purified by column chromatography over silica gel using a mixture of trichloromethane and methanol, saturated with ammonia, (95:5 by volume) as eluent. The pure fractions were collected and the eluent was evaporated. The residue was crystallized from 2,2'-oxybispropane. The product was filtered off and dried at 80° C., yielding 2.45 parts (83.5%) of trans-4-[[2-(acetylamino)-6-methoxybenzoyl]amino]-3-hydroxy-N,N,γ-trimethyl-α,α-diphenyl-1-piperidinebutanamide; mp. 146.5° C. (compound 61).

Provenance & Evidence