TBDPS and Br-TBDPS Protecting Groups as Efficient Aryl Group Donors in Pd-Catalyzed Arylation of Phenols and Anilines

It is shown that the TBDPS protecting group can serve as an efficient phenyl. group donor for o-bromophenols via Pd-catalyzed C-H arylation followed by a routine TBAF deprotection of the resulting silacycles. Employment of the newly designed Br-TBDPS protecting group in the same sequence allows for a facile introduction of a phenyl group at the ortho position of phenols and anilines. Alternatively, switching desilylation to oxidation in the last step allows the conversion of forming silacycles into valuable o-biphenols.