Potassium Carbonate → tert-Butyl 4-ethynylpiperidine-1-carboxylate

Participants

Reaction Steps

At 0 C., to a stirred mixture of 4-formyl-piperidine-1-carboxylic acid tert-butyl ester (358 mg, 1.68 mmols) and potassium carbonate (464 mg, 3.36 mmols) in methanol (16 ml) was added dropwise a solution of (1-diazo-2-oxo-propyl)-phosphonic acid dimethyl ester (323 mg, 1.68 mmols) in methanol (2 ml). The resulting mixture was stirred at room temperature overnight, filtered and concentrated. The residue was chromatographed on silica gel using a solution of ethyl acetate in hexanes (1:5) to provide the title compound (308 mg, 88%) as colorless crystals. LCMS m/e (154, M−t-Bu+2H). (J. Am. Chem. Soc. 2003, 125, 3714.)

Provenance & Evidence