Oxalyl chloride → 1-Pyrrolidinecarboxylic acid, 2-(chlorocarbonyl)-, phenylmethyl ester

Participants

Reaction Steps

Oxalyl chloride (1.21 mL, 14.0 mmol) was added dropwise (15 minutes) to a 0° C. solution of N-carbobenzyloxy-D,L-proline (2.50 g, 10.0 mmol), dimethylformamide (1 drop, cat.) and methylene chloride (anhydrous, 25 mL) under a nitrogen atmosphere. The mixture was removed from the ice-bath and stirred at ambient temperature for 1 h. The reaction mixture was concentrated to afford 2.63 g (98%) of 2-chlorocarbonyl-pyrrolidine-1-carboxylic acid benzyl ester as an orange oil. The product was used directly in subsequent steps.

Provenance & Evidence