Enantioselective Preparation of a Chiral-at-Metal Cp*Ir(NHC) Complex and Its Application in the Catalytic Diboration of Olefins

The reaction of (S,S)-1,3-di(methylbenzyl)imidazolium
chloride with [Cp*IrCl2]2 in the presence of NaOAc affords
the diastereoselective formation of a Cp*Ir(NHC) complex with
a chelating ligand coordinated through the carbene and the
ortho-position of one of the phenyl groups. The crystal structure
of this new enantiomerically pure compound is described. The
complex has been used in the catalytic diboration of olefins,
providing high efficiencies and chemoselectivities on the
organodiboronate products.