Copper-Catalyzed Selective C–H Carboxylation of Alkenes with CO₂

Key words

copper catalysis - borylation - carbonylation - tandem reaction

Significance

Zhang and Hou report the highly selective C–H carboxylation of styrene derivatives to access α,β-unsaturated esters using copper catalysis. In-depth mechanistic studies reveal novel catalytic activity and a potential pathway involving two catalytic cycles linked by an in situ generated copper-alkoxide species (A). Notably, the authors propose CO₂ acts as a multitasking carboxylation reagent.

Comment

Compound A enables borylcupration of the alkene to generate intermediate C. The β-H elimination generates vinyl boronate F and a copper hydride species, which instantly reacts with CO₂ to form copper formate E. Formation of E enables regeneration of A and initiates the tandem catalytic cycle. Transmetalation of A and F forms the nucleophilic organocopper G. CO₂ insertion and metathesis with the alkoxide base regenerates A, while product J is obtained following protolysis and methylation.

Publikationsverlauf

Artikel online veröffentlicht:
13. Februar 2023