Cyclohexylamine → 3-Bromo-1-cyclohexylpyrrolidin-2-one

Participants

Reaction Conditions

Reaction Steps

Dissolve 2,4-dibromo-butyryl chloride (17.0 g, 64.3 mmol) in chloroform (3 ml) and add to a mixture of cyclohexylamine (7.65 g, 77.2 mmol) in chloroform (20 mL) and H2O (3 mL) at 0° C. Add sodium hydroxide (5.92 g, 147.9 mmol) slowly while keeping the reaction temperature below 10° C. Stir for 1 hour. Wash the organic layer with 0.5M hydrochloride and brine. Dry over sodium sulfate, filter, and concentrate. Place the residue in THF (200 mL) and cool to 0° C. Add sodium hydride (1.02 g, 42.6 mmol) and stir for two days. Add additional sodium hydride (1.02 g, 42.6 mmol) and stir for 3 days. Pour onto water and ice and extract with methylene chloride. Dry over sodium sulfate, filter, and concentrate to yield 6.36 g (34%) of the title compound: NMR (CDCl3) δ 4.41 (dd, 1H), 3.94 (m, 1H), 3.48 (m, 1H), 3.33 (m, 1H), 2.51 (m, 1H), 2.30 (m, 1H), 1.82 (m, 3H), 1.70 (m, 2H), 1.38 (m, 4H), 1.11 (m, 1H).

Provenance & Evidence