Benzyl chloroformate → 1-Benzyl 3-(4-methoxyphenyl)methyl (3RS,4SR)-3-[2-(tert-butoxy)-2-oxoethyl]-4-methylpyrrolidine-1,3-dicarboxylate

Participants

Reaction Steps

A solution of (4-methoxyphenyl)methyl (3RS,4SR)-1-benzyl-3-[2-(tert-butoxy)-2-oxoethyl]-4-methylpyrrolidine-3-carboxylate obtained in Example 2g (18 g, 39.7 mmol) in dichloromethane (85.7 ml) was adjusted to an internal temperature of 10 to 20° C., and benzyl chloroformate (11.9 ml, 79.4 mmol) was added thereto. After returning to mom temperature and stirring for 0.5 hour, the reaction mixture was concentrated directly. The resulting crude product was purified by column chromatography (silica gel, elution solvent: ethyl acetate/heptane) to give the title compound (12.89 g, yield: 65.3%).

Provenance & Evidence