Ruthenium(II)-Catalyzed Ortho-C-H Alkylation of Naphthylamines with Diazo Compounds for Synthesis of 2,2-Disubstituted π-Extended 3-Oxindoles in Water.

Ruthenium(II)-catalyzed ortho-C-H alkylation of naphthylamines with diazo compounds for the synthesis of 2,2-disubstituted π-extended 3-oxindoles has been developed. The method represents the first example of C-H alkylation via carbenoid insertion in water as a sustainable solvent. The procedure includes an inexpensive ruthenium catalyst as well as aqueous media and results in the release of benign N2. The π-extended 3-oxindole products exhibit favorable antitumor properties and remarkable fluorescent properties in aqueous solution for fluorescent imaging.