Conjugate Reduction of α,β‐Unsaturated Carbonyl and Carboxyl Compounds with Poly(methylhydrosiloxane) Catalyzed by a Silica‐Supported Compact Phosphane–Copper Complex

A silica‐supported, cage‐type, compact phosphane (Silica‐SMAP) was used for the copper‐catalyzed conjugate reduction of α,β‐unsaturated carbonyl and carboxyl compounds with poly(methylhydrosiloxane) (PMHS). The heterogeneous catalyst system showed high activity and chemoselectivity, and was easily separable from the reaction mixture after the reaction. Furthermore, the catalyst was reusable without loss of its high catalytic activity or selectivity.