Modular Approach to Reductive C-sp2-H and C-sp3-H Silylation of Carboxylic Acid Derivatives through Single-Pot, Sequential Transition Metal Catalysis

摘要

We report a modular approach to catalytic reductive C-sp2-H and C-sp3-H silylation of carboxylic acid derivatives encompassing esters, ketones, and aldehydes. Choice of either an Ir(I)/Rh(I) or Rh(I)/Rh(I) sequence leads to either exhaustive reductive ester or reductive ketone/aldehyde silylation, respectively. Notably, a catalyst-controlled direct formation of doubly reduced silyl ethers is presented, specifically via Ir-catalyzed exhaustive hydrosilylation. The resulting silyl ethers undergo C-sp2-H and benzylic C-sp3-H silylation in a single vessel.