Boron tribromide → HCID 14254546, compound

Participants

Reaction Steps

In 100 ml of dried dichloromethane was dissolved 1.7 g of ethyl {[5-chloro-3-(2-hydroxyphenyl)-4-oxo-4H-1-benzopyran-7-yl]oxy}acetate, and the solution was cooled with dry ice-acetone. Three milliliters of boron tribromide were added to the cooled solution in small portions, and the resulting mixture was refluxed for 3 hours. After cooling, the solvent was removed by distillation under reduced pressure, and to the residue was added dilute hydrochloric acid. The precipitated crystals were collected by filtration, washed with water, air-dried, and recrystallized from ethanol to obtain 1.0 g of the entitled compound having a melting point of 188°-189° C. (with decomposition).

Provenance & Evidence