Carboxylations of (Hetero)Aromatic C-H Bonds Using an Alkyl Silyl Carbonate Reagent.

In this paper, we report that the use of an alkyl silyl carbonate reagent combined with CsF and 18-crown-6 facilitates efficient direct carboxylations of (hetero)aromatic C-H bonds. This system also enables benzylic carboxylation of a toluene derivative and double carboxylation of methyl heteroarene. The carbonate reagent is characterized by its ease of handling and storage. Moreover, we demonstrate the application of this system in C-labeling experiments.