Mesoporous silica KIT-6 supported superparamagnetic CuFe2O4 nanoparticles for catalytic asymmetric hydrosilylation of ketones in air

摘要

A diverse range of prochiral ketones were reduced in air with high yields and good-to-excellent enantio-selectivities (up to 97% ee) in the presence of a heterogeneous catalyst system, which was in situ formed from catalytic amounts of superparamagnetic CuFe2O4 nanoparticles supported on mesoporous silica KIT-6 and non-racemic dipyridylphosphine ligand, the stoichiometric hydride donor polymethylhydro-siloxane (PMHS) as well as certain amounts of additives. The magnetically separable catalysts could be efficiently reused 4 times without apparent loss of both the activity and enantioselectivity.