Asymmetric hydrogenation of tri-substituted alkenes with Ir-NHC-thiazole complexes

An efficient chiral N-heterocyclic carbene ligand for the Ir-catalyzed asymmetric hydrogenation of largely unfunctionalized tri-substituted olefins has been developed. The Ir-NHC-thiazole catalyst is able to reduce a large variety of substrates with excellent conversions and good enantioselectivities with ee’s ranging from 34% to 90%, depending on the geometry around the double bond of the substrates.