Cationic iridium-catalyzed enantioselective activation of secondary sp3 C-H bond adjacent to nitrogen atom

A cationic Ir(I)-tolBINAP complex catalyzed an enantioselective C-C bond formation, which was initiated by secondary sp3 C-H bond cleavage adjacent to nitrogen atom. A wide variety of 2-(alkylamino)pyridines and alkenes were selectively transformed into the corresponding chiral amines with moderate to almost perfect enantiomeric excesses. Alkynes were also investigated as coupling partners. The effect of alkyl structure in substrates and directing groups were studied. This transformation represents the first example of a highly enantioselective C-H bond activation of a methylene group, not at allylic or benzylic position.

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