Phosgene → rac-(4S*,5R*)-4,5-bis(4-chlorophenyl)-2-(4-(tert-butyl)-2-ethoxy-phenyl)-4,5-dimethyl-4,5-dihydro-1H-imidazole-1-carbonyl chloride

Participants

Reaction Steps

To a solution of rac-(4S*,5R*)-4,5-bis(4-chlorophenyl)-2-(4-(tert-butyl)-2-ethoxy-phenyl)-4,5-dimethyl-4,5-dihydro-1H-imidazole (710 mg, 1.43 mmol, example 2) and triethylamine (400 uL, 2.86 mmol) in 12 mL of dichloromethane at 0° C. was added 1.13 mL of 1.9 M phosgene in toluene solution (Fluka). After stirring for 30 min the mixture was taken up in dichloromethane and washed with water, dried over anhydrous sodium sulfate, filtered and concentrated under reduced pressure. Purification by chromatography on silica gel, eluting with hexane-ethyl acetate (4:1) provided 689 mg of rac-(4S*,5R*)-4,5-bis(4-chlorophenyl)-2-(4-(tert-butyl)-2-ethoxy-phenyl)-4,5-dimethyl-4,5-dihydro-1H-imidazole-1-carbonyl chloride as a white solid.

Provenance & Evidence