Methyltransferase Activity of an Iridium Center with Methylpyridinium as Methylene Source

Methyltransferase Activity of an Iridium Center with Methylpyridinium as Methylene Source:

Hop on, hop off: an iridium center transfers a methyl group from pyridinium to an aryl unit, using exclusively the pyridine-bound methyl group as a mild methylene source. The reaction also involves cleavage of an unactivated C(aryl)H bond and nitrile solvent activation. The process is reminiscent of DNA methylation and entails the formation of two new C(sp²)C(sp³) bonds within the metal coordination sphere (see scheme).