Ir-Catalyzed Heterocyclization by C-H Bond Activation through Transfer Hydrogenation

In this reaction, JV-benzylideneimine was formed initially by the reaction of aniline with the aldehyde, and the iridium complex catalyst serves as a Lewis acid. 

Ir-Catalyzed Heterocyclization by C-H Bond Activation through Transfer Hydrogenation 

Iridium-catalyzed transfer hydrogenation of alcohol substrates also provides a useful method of C-C bond formation. 

Ir-Catalyzed Reaction of Anilines with Diols to Give 2,3-Dlsubstltuted Indoles 

Madsen and coworkers reported Ir-catalyzed synthesis of 2,3,-disubstituted indoles from anilines and diols. A typical reaction involved the treatment of aniline with 2,3-butanediol in the presence of a catalytic amount of [Cp IrCl2]2 (lmol%) combined with methanesulfonic acid (5mol%) at 170 °C and gave 2,3-dimethylindole in 76% yield [160]. The reaction is proposed to proceed by the 

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