4-Chlorobenzoyl chloride → 4-(4-Chloro-benzoylamino)-4-cyano-piperidine-1-carboxylic acid tert-butyl ester

Participants

Reaction Steps

To a solution of 4-amino-4-cyano-piperidine-1-carboxylic acid tert-butyl ester (1.25 g, 5.55 mmol, 1.0 equiv; prepared as described in WO 03/104 236 A1 (Bristol-Myers Squibb Company); [CAS RN 331281-25-5]) in dichlormethane (30 mL) and triethylamine (1.20 mL) was added 4-chloro-benzoyl chloride (1.09 g, 6.21 mmol, 1.12 equiv; commercially available) and the reaction stirred at rt overnight. A solution of 1 M NaOH (10 mL) was added and the reaction mixture extracted with ethyl acetate. The combined organic phases were washed with water and a sat. solution of NaCl, dried over MgSO4 and concentrated by evaporation under reduced pressure. The crude material was crystallized from a mixture of hexane/ethyl acetate yielding 0.71 g (44%) of the title compound as white crystals. 1H NMR (300 MHz, CDCl3): δ 1.46 (s, 9H), 1.85 (t, J=10.2 Hz, 2H), 2.45 (br s, 2H), 3.24 (t, J=11.8 Hz, 2H), 3.99 (br d, J=13.5 Hz, 2H), 6.87 (s, 1H), 7.36 (d, J=8.4 Hz, 2H), 7.69 (d, J=8.4 Hz, 2H). MS (ISP): 364.4 [M+H]+.

Provenance & Evidence