1,2-Dichloroethane → 6-Bromo-5,7-dimethyl-4-(3-nitrophenyl)-2H-chromen-2-one

Participants

Reaction Steps

To a stirred solution of 4-bromo-3,5-dimethylphenyl 3-(3-nitrophenyl)propiolate (6-2) (15.96 g, 42.65 mmol) in CH2Cl2 (100 mL) was added TFA (10 mL) and Pd(OAc)2 (480 mg, 2.14 mmol) at 0° C. The mixture was warmed to room temperature and stirred for 4.5 h. To the mixture was added 1,2-dichloroethane and concentrated. Then toluene was added and concentrated. To the concentrate added toluene, dichloromethane and hexane, and the precipitated solid was collected by filtration. The solid was washed with hexane and dried to give the title compound 6-3 (15.51 g, 97% yield) as a brown solid.

Provenance & Evidence