Acetic Acid → (3R*,4S*)-1-Benzyl-3-[2-(tert-butoxy)-2-oxoethyl]-4-methylpyrrolidine-3-carboxylic acid

Participants

Reaction Conditions

Reaction Steps

A mixture of (3R*,4S*)-3-[2-(tert-butoxy)-2-oxoethyl]-4-methylpyrrolidine-3-carboxylic acid obtained in Example 1i (1.8 g, 7.4 mmol), benzaldehyde (1.51 ml, 14.8 mmol), acetic acid (0.635 ml, 11.1 mmol), sodium triacetoxyborohydride (3.14 g, 14.8 mmol) and methanol (35 ml) was heated at 40° C. for 38 hours and 30 minutes. The reaction mixture was concentrated, and the resulting residue was purified by silica gel column chromatography (ODS silica gel, elution solvent: water/methanol) to give the title compound as Lot A (584 mg) and Lot B (708 mg).

Provenance & Evidence