Methanol → 1-N-Boc-4-Piperidinecarboxylic acid methyl ester

Participants

Reaction Steps

To an ice cold solution of N-t-butoxycarbonyl isonipecotic acid (8.8 g, 34.9 mmol), in a 10% mixture of methanol in benzene (250 ml), was added a 2.0 M solution of trimethylsilyldiazomethane in hexanes, dropwise, until a consistent yellow color was obtained (~30 ml). After vigorous gas evolution had ceased, cooling was removed and the reaction mixture stirred for 1 h at room temperature. The mixture was then treated dropwise with glacial acetic acid until all yellow color had dissipated. It was then stirred 15 min. and concentrated in vacuo to a pale yellow oil. This material was purified by column chromatography on silica with 20% EtOAc/hexane as eluent. The appropriate fractions were combined and concentrated in vacuo to afford the product as a colorless oil.

Provenance & Evidence