Dimethyl Sulfoxide → Trans-4-amino-1-methyl-cyclohexanol

Participants

Reaction Conditions

Reaction Steps

4-(Dibenzylamino)cyclohexanone. A solution of dimethyl sulfoxide (5.77 mL, 81 mmol) in methylene chloride (20 mL) was added dropwise, to a solution of oxalyl chloride (3.26 mL, 37.2 mmol) in methylene chloride (150 mL) stirring at −78° C. After stirring for 15 min at −78° C., a solution of trans-4-(dibenzylamino)cyclohexanol (10.0 g, 33.9 mmol) in methylene chloride (100 mL) was added dropwise. After stirring at −78° C. for another 15 min, triethylamine (23.59 mL, 169 mmol) was added dropwise and the reaction was allowed to warm to room temperature and stirred for 16 h. The reaction mixture appeared as a suspension and was washed with brine (100 mL). The organic layer was separated, dried over magnesium sulfate and concentrated to give a colorless oil that was purified using silica gel flash column chromatography (5-100% ethyl acetate in hexanes) to give the title compound as a colorless oil (8.11 g, 82% yield). 1H NMR (400 MHz, DMSO-d6) δ (ppm) 7.35-7.39 (m, 4H), 7.28-7.33 (m, 4H), 7.18-7.24 (m, 2H), 3.61 (s, 4H), 2.89-2.99 (m, 1H), 2.26-2.38 (m, 2H), 2.14-2.24 (m, 2H), 2.06 (td, J=2.81, 6.43 Hz, 2H), 1.81 (qd, J=4.27, 12.49 Hz, 2H). Rf=0.36 (TLC, 20% ethyl acetate in hexane); MS (ESI) m/z 294.4 [M+1]+.

Provenance & Evidence