Highly stable Cp*-Ir(III) complexes with N-heterocyclic carbene ligands as C-H activation catalysts for the deuteration of organic molecules

The preparation of a series of complexes of the type Cp*IrX2(NHC) provides effective catalysts for the H/D exchange of a wide range of organic molecules in methanol-d(4). The reaction proceeds with higher yields under milder reaction conditions than previous Cp*Ir systems reported thus far. For comparative purposes, we also studied the catalytic activity of Cp*IrCl2(PMe3) under the same reaction conditions. The molecular structures of two of the new Cp*Ir(NHC) complexes are described.