Boron tribromide → N-{4-[(4-Hydroxy-phenyl)-(3,3,5,5-tetramethylcyclohexylidene)-methyl]phenyl}-methanesulfonamide

Participants

Reaction Conditions

Reaction Steps

To a solution of N-{4-[(4-methoxy-phenyl)-(3,3,5,5-tetramethyl-cyclohexylidene)methyl]-phenyl}-methanesulfonamide (180) (0.25 g, 0.585 mmol) in dry dichloromethane (20 mL) was slowly added BBr3 (1 N in dichloromethane) (1.75 mL, 1.75 mmol) at −5 to 0° C. The reaction mixture was stirred at −5 to 0° C. under nitrogen for 3 h. The reaction mixture was poured onto ice and stirred for several minutes. The quenched reaction mixture was transferred to a separatory funnel and the layers were separated. The aqueous layer was extracted with EtOAc and the organic extracts were combined, washed with brine, dried over MgSO4, filtered, and concentrated to give an off white solid. The solid was triturated with hexanes followed by dichloromethane. The product was filtered, washed with methanol, and dried to give 0.174 g (72%) of compound 181 as a white powder. 1H NMR (400 MHz, DMSO-d6): δ 0.86 (s, 12H), 1.23 (s, 2H), 1.86 (s, 2H), 1.89 (s, 2H), 2.94 (s, 3H), 6.64 (d, J=8.6 Hz, 2H), 6.90 (d, J=8.5 Hz, 2H), 7.06 (s, 2H), 7.07 (s, 2H), 9.25 (s, 1H), 9.64 (s, 1H). HRMS (ESI) calcd for C24H30NO3S: 412.1946 (M−H)−. Found: 412.1942.

Provenance & Evidence