Arene-Ligand-Free Ruthenium(II/III) Manifold for meta-C-H Alkylation: Remote Purine Diversification

meta-Selective C-H alkylations of bioactive purine derivatives were accomplished by versatile ruthenium catalysis. Thus, the arene-ligand-free complex [Ru(OAc)(2)(PPh3)(2)] enabled remote C-H functionalizations with ample scope and excellent levels of chemo- and positional selectivities. Detailed experimental and computational mechanistic studies provided strong support for a facile C-H activation within a ruthenium(II/III) manifold.