Carboxyl-Assisted meta-Selective C-H Functionalizations of Benzylsulfonamides.

A protocol of carboxyl-group-assisted, Pd(II)-catalyzed remote meta-C(sp2)-H olefination and arylation of benzylsulfonamides has been developed. It was supposed to proceed through a κ2 coordination of the carboxyl group to the Pd center. These findings demonstrated the versatility of carboxyl-assisted remote meta-C-H activation strategy and might stimulate the exploration of novel reactivity and selectivity of other traditional chelating groups in different contexts.