Dimethylformamide → 7-bromo-4-chloro-2H-chromene-3-carbaldehyde

Participants

Reaction Steps

Anhydrous dimethylformamide (8.18 ml, 106 mmol) was taken in a two-necked round bottomed flask fitted with a dropping funnel. POCl3 (7.23 ml, 78 mmol) was added to it by keeping the flask in an ice bath and after the completion of addition, the ice bath was removed and the mixture was stirred at RT for 1 hr. 7-bromochroman-4-one (16 g, 71 mmol) was dissolved in 200 ml of chloroform and was slowly added to the flask kept on an ice bath, and after completion of the addition, the ice bath was removed and the reaction mixture was stirred overnight at 60° C. The reaction was brought to RT and ice cold water was added to it and the compound was extracted with chloroform. The organic layer was washed with 10% NaHCO3 solution and dried over Na2SO4, filtered and concentrated to obtain the crude title compound (15.1 g, 78%) which was sufficiently pure enough for the next step. m/z 273.9 (M+)

Provenance & Evidence