DOI 10.5012/bkcs.2011.32.8.2865 Pd-Catalyzed ortho-Methylation of Acetanilides via Directed C-H Activation†

In view of atom economic and eco-friendly process, direct activation and subsequent functionalization of C-H bond in aromatic compounds have attracted the most attention as an efficient synthetic method with broad applications, providing a powerful alternative to the classical coupling reaction using preformed organometallic reagents.1 In general, regioselectivity of C-H bond functionalization can be achieved through the introduction of coordinating functionality for synthetic purposes.2 Recently, we reported a highly effective Pd-catalyzed ortho-alkenylation of acetanilides with unprecedented substrate scope (Scheme 1).3 Our continued interest in Pd-catalyzed C-H bond functionalization prompted us to investigate the possibility of a Pd-catalyzed ortho-alkylation of acetanilides. While intensive ex-ploration and significant advances in PdII-catalyzed regioselective C(sp2)-C(sp2) bond formation have been made, very few ex