1-Chloroethyl chloroformate → Hydrochloric Acid

Participants

Reaction Conditions

Reaction Steps

To a solution of 1′-benzyl-3H-spiro[isobenzofuran-1,4′-piperidin]-3-one 1b (6 g, 20.4 mmol) in dichloromethane (30 mL) was added dropwise 1-chloroethyl chloroformate (2.9 g, 20.4 mmol). The mixture was stirred at 25° C. for 5 hr and then was concentrated to dryness under reduced pressure. The residue was dissolved in methanol and the mixture was heated to reflux for 30 min. The mixture was concentrated to dryness and ether was added. The precipitated solid was collected by filtration and washed with ether, dried in air to obtain 3H-spiro[isobenzofuran-1,4′-piperidin]-3-one 1c as its HCl salt (3.6 g). 1H-NMR (400 MHz, DMSO-d6) δ 9.16 (br, 2H), 7.86-7.81 (m, 2H), 7.63 (t, J=7.6 Hz, 1H), 7.56 (d, J=7.2 Hz, 1H), 3.39-3.42 (m, 2H), 3.11-3.14 (m, 2H), 2.47-2.48 (m, 2H), 1.85 (d, J=14.4 Hz, 2H). MS (ESI) m/z (M+H+): 203.24.

Provenance & Evidence