Dimethyl Sulfoxide → (R)-3-(dibenzylamino)cyclohexanone

Participants

Reaction Conditions

Reaction Steps

Oxalyl chloride (3.81 mL, 43.6 mmol) was dissolved in dry DCM (150 mL) and cooled to −78° C. DMSO (6.75 mL, 95.0 mmol) in dry DCM (20 mL) was added dropwise to the reaction mixture and the reaction was stirred for 15 minutes at −78° C. Next, (1S,3R)-3-(dibenzylamino)-cyclohexanol (11.7 g, 39.6 mmol) in dry DCM (100 mL) was added dropwise using an addition funnel and the reaction was stirred at −78° C. for 15 minutes. TEA (27.6 mL, 198 mmol) was then added and the reaction was stirred at −78° C. for 1 h. The dry-ice bath was removed and the reaction mixture was allowed to warm to room temperature and stir overnight. The reaction mixture was washed with brine (5×500 mL), the organic layer was separated, dried over magnesium sulfate and concentrated to yield (R)-3-(dibenzylamino)cyclohexanone (10.2 g, 88%) as a tan solid. 1H NMR (400 MHz, DMSO-d6) δ ppm 7.26-7.39 (m, 8H), 7.17-7.25 (m, 2H), 3.56-3.70 (m, 4H), 2.71-2.81 (m, 1H), 2.60-2.69 (m, 1H), 2.25-2.42 (m, 2H), 2.04-2.11 (m, 1H), 1.88-1.99 (m, 2H), 1.69-1.82 (m, 1H), 1.18-1.33 (m, 1H); MS (ESI) m/z 294.4 [M+1]+.

Provenance & Evidence