Rare-earth-catalyzed C-H bond addition of pyridines to olefins.

An efficient and general protocol for the ortho-alkylation of pyridines via C-H addition to olefins has been developed, using cationic half-sandwich rare-earth catalysts, which provides an atom-economical method for the synthesis of alkylated pyridine derivatives. A wide range of pyridine and olefin substrates including α-olefins, styrenes, and conjugated dienes are compatible with the catalysts.