Water → 1-(Benzyloxycarbonyl)-4-phenylpiperidine-4-carboxylic acid

Participants

Reaction Conditions

Reaction Steps

A mixture of 37.7 g of 4-carboxy-4-phenylpiperidine p-toluenesulphonate, 53.3 g of 30% aqueous NaOH solution and 250 ml of water is cooled to 5° C. A solution of 18 g of benzyl chloroformate in 60 ml of acetone is added rapidly at 5° C., and the mixture is left stirring overnight while allowing the temperature to rise to RT. The reaction mixture is washed twice with ether and, after settling has taken place, the aqueous phase is separated and acidified to pH 1 by adding concentrated HCl and then 2N HCl. The precipitate formed is drained, dried, taken up in ether and drained again. 30.6 g of the expected product are obtained, m.p.=142°-144° C.

Provenance & Evidence