(4-Amino-5-chloro-2,3-dihydrobenzofuran-7-yl)(1H-imidazol-1-yl)methanone → (+/-)-1,1-Dimethylethyl cis-4-[[[(4-amino-5-chloro-2,3-dihydro-7-benzofuranyl)carbonyl]amino]methyl]-3-hydroxy-1-piperidinecarboxylate

Participants

Reaction Conditions

Reaction Steps

A mixture of intermediate (1-f) (0.09 mol) and intermediate (3-c) (0.087 mol) in ACN (600 ml) was stirred and refluxed for 1 hour. The reaction mixture was cooled to 0° C., and the solvent was evaporated. The residue was partitioned between DCM and water. The organic layer was separated, dried, filtered and the solvent was evaporated. The residue was purified by column chromatography over silica gel (eluent: CH2Cl2/(CH3OH/NH3) 97/3). The pure fractions were collected and the solvent was evaporated. The residue was crystallized from ACN. The precipitate was filtered off and dried), yielding 28.7 g (78%) of (±)-1,1-dimethylethyl cis-4-[[[(4-amino-5-chloro-2,3-dihydro-7-benzofuranyl)carbonyl]amino]methyl]-3-hydroxy-1-piperidinecarboxylate (interm. 4. mp. 218° C.).

Provenance & Evidence