Catalytic asymmetric Henry reaction using copper(II) chiral tridentate Schiff-base complexes and their polymer-supported complexes

Abstract

A series of chiral tridentate Schiff-base ligands and their polymer-supported ligands were conveniently prepared and introduced as copper(II) chiral complexes for the asymmetric Henry reaction. The structures of these ligands have been characterized by IR, 1 H NMR, 13 C NMR and MS. The experimental results showed that the corresponding b-nitro alcohols were obtained in moderate to high yields (up to 98%) with up to 98% ee under mild conditions. The complex catalyst forming from copper(II) polymer-supported ligands could be recycled by a simple filtration and reused 6 times at least with similar good catalytic effect (about 94% yield and 90% ee).

Recent Advances in the Catalytic Applications of Chiral Schiff‐Base Ligands and Metal Complexes in Asymmetric Organic Transformations

“…In 2016, Song and his group reported a Cu(II)-tridentate Schiff base complex 134-139 for the asymmetric Henry reaction. [108] The catalyst was supported on a polymer matrix. Thus, the use of polymer support provides the advantage of its easy reusability and recyclability.…”