Methyl iodide → 4-Cbz-1-methyl-2-piperazinone

Participants

Reaction Steps

To a solution of 3-oxo-piperazine-1-carboxylic acid benzyl ester (2.00 g, 8.54 mmol) in DMF (30 mL) was added KOtBu (1.54 g, 13.7 mmol) under Ar. The resulting solution was stirred at room temperature for 15 min and cooled to 0° C. MeI (0.85 mL, 14 mmol) was then added dropwise. The reaction mixture was allowed to warm to room temperature and stirred for 3 h. DMF was removed in vacuo and the residue was chromatographed on silica (5-50% EtOAc:hexane) to obtain the title compound (1.40 g, 66%). 1H-NMR (CDCl3; 400 MHz): δ 7.32 (m, 5H), 5.13 (s, 2H), 4.13 (s, 2H), 3.70 (m, 2H), 3.34 (m, 2H), 2.97 (s, 3H)

Provenance & Evidence