Benzyl chloroformate → Benzyl 4-cyanopiperidine-1-carboxylate

Participants

Reaction Steps

A solution of 4-cyanopiperidine (5.00 g) in 10% aqueous sodium carbonate solution (100 mL) was cooled to 0° C. and treated dropwise with benzyl chloroformate (9.30 g). The resulting mixture was warmed to room temperature and stirred for 16 hours. The biphasic mixture was extracted with ethyl acetate. The organic extracts were washed with water and brine, combined, dried, filtered and evaporated. The resulting oil was purified by chromatography, with ethyl acetate:hexane (gradient 1:4, 1:2) as eluent, to give the protected piperidine as a clear oil (9.64 g); MS: m/z=245(M+1); NMR (CDCl3): 7.35 (m, 5), 5.13 (s, 2), 3.71 (m, 2), 3.44 (m, 2), 2.81 (m, 1), 1.88-1.60 (m, 4).

Provenance & Evidence