Dimethylformamide → HCID 13393789, compound

Participants

Reaction Steps

As in example 1, but using 10 g 3'-fluoro-flavanone, 100 ml dimethylformamide and 15 ml phosphorous oxychloride. Reaction time is two hours at 50° C. After hydrolysis a precipitate formed which is filtered, washed with water and dried over phosphorous pentoxyde. The residual solid is recrystallised in a mixture of ethanol and water and pure yellow crystalline 4-chloro-3'-fluoro-3-formyl-flav-3-ene is obtained; m.p. 97°-99° C.

Provenance & Evidence