Benzyl chloroformate → 1-(Phenylmethyl) (3R)-1,3-piperidinedicarboxylate

Participants

Reaction Conditions

Reaction Steps

A solution of (R)-piperidine-3-carboxylic acid (XXVII) (5.0 g, 39 mmol) in a mixture of 50 ml of THF and 20 ml of water was cooled to 0° C. and sodium bicarbonate (6.5 g, 77.4 mmol) and benzyl chloroformate (8.0 g, 46.4 mmol) were added simultaneously. The reaction mixture was stirred at 0° C. for 30 min and at room temperature for 3 hours and concentrated under reduced pressure. The remaining aqueous phase was extracted with ethyl ether to remove excess of benzyl chloroformate, then it was acidified with 1 M HCl solution to pH 6 followed by extraction with ethyl acetate. The organic layer was separated, dried over sodium sulfate and evaporated to provide (R)-piperidine-1,3-dicarboxylic acid 1-benzyl ester (XXVIII) (3.7 g, 36%).

Provenance & Evidence