HCID 21279521, compound → HCID 21279508, compound

Participants

Reaction Steps

The product of stage (a) (57.9 g) was added portionwise to polyphosphoric acid (250 ml) at about 100° C. with stirring. Heating was continued for 30 minutes and the solution was then added to ice-water (1 l) and ethyl acetate (300 ml). The ethyl acetate solution was separated, and the aqueous phase was extracted with ethyl acetate. The organic phases were combined, washed with aqueous bicarbonate and water, dried and run down to give 49.3 g of crude product. Recrystallisation from ethanol gave 45.1 g of desired product, mp 85°-87° C.

Provenance & Evidence