Iron‐Catalyzed Room Temperature Cross‐Couplings of Bromophenols with Aryl Grignard Reagents.

Herein we report a room temperature Fe‐catalyzed coupling reaction of various bromophenols with aryl Grignard reagents, which exhibits a wide substrate scope and high functional group tolerance. For the first time, the combination of simple Fe(acac)3/PBu3/Ti(OEt)4 has been used as an effective catalyst for the biaryl couplings of bromophenols or their Na or K salts with debromination and etherification side reactions being well suppressed. Various biphenols including natural product garcibiphenyl C as well as pharmaceutical diflunisal and its ethyl ester were facilely synthesized using the present protocol. [ABSTRACT FROM AUTHOR]