Carbon tetrabromide → tert-Butyl 4-(bromomethyl)piperidine-1-carboxylate

Participants

Reaction Conditions

Reaction Steps

A solution of 4-hydroxymethyl-piperidine-1-carboxylic acid tert-butyl ester (2.30 g, 10.7 mmol) and carbon tetrabromide (4.43 g, 13.4 mmol) in CH2Cl2 (40 mL) is cooled to 0° C. Triphenylphosphine (4.21 g, 16.0 mmol) is added and the reaction is stirred at 25° C. for 1 h. The reaction is concentrated and ether is added to the residue. The mixture is filtered and washed with ether. The filtrate is concentrated and purified by column chromatography (silica, 20% EtOAc/hexane) to provide 4-bromomethyl-piperidine-1-carboxylic acid tert-butyl ester as a crystaline solid upon standing. Mp 48-50° C.; 1H NMR (300 MHz, CDCl3) δ 4.13 (bm, 2H), 3.29 (d, 2H), 2.70 (dd, 2H), 1.85-1.73 (m, 3H), 1.46 (s, 9H), 1.28-1.13 (m, 2H); MS (EI) 277 (M)+.

Provenance & Evidence