Facile synthesis of α,β-acetylenic ketones and 2,5-disubstituted furans: consecutive activation of triple and double bond with ZnBr2 toward the synthesis of furan ring

α,β-Acetylenic ketones were synthesized from the reaction of acid chlorides and acetylenic compounds in the presence of ZnBr2 and DIEA in acetonitrile. From the acetylenic ketones having nearby methylene unit, 2,5-disubstituted furan derivatives could be synthesized under the same reaction conditions.