One-step Synthesis Of Benzofunans From α-haloketones And Phenols

Benzofurans,especially naphthofurans,are valuable heterocyclic compounds because of their natural existence and significant biological activity.Therefore,the synthesis of these compounds has always been a hot topic in the field of the organic chemical synthesis.A variety of methods have been explored for the synthesis of benzofurans.One of the most convenient strategies is that using phenol as starting material to react with α-haloketone to form α-aryl carbonyl compound intermediate,and then acid-catalyzed dehydration to construct the furan ring.Therefore,our work is focused on the one-step synthesis of benzofurans with high regioselectivity.Reported here is the direct synthesis of naphthofurans and benzofurans from readily available phenols and α-haloketones promoted by titanium tetrachloride which combined Friedel-Crafts-like alkylation and intramolecular cyclodehydration into one step.The research work mainly includes model reaction optimization,screening of naphthols and phenols with different α-haloketones.This simple protocol allows for the formation of a variety of high value naphthofurans and benzofurans within which a series of cyclic and acyclic groups are readily incorporated.This process demonstrates advantages of high levels of regioselectivity,broad substrate scope,and moderate to excellent yields.