Porous Rh/BINAP polymers as efficient heterogeneous catalysts for asymmetric hydroformylation of styrene: Enhanced enantioselectivity realized by flexible chiral nanopockets

Abstract A new chiral monomer, ( S )-5,5′-divinyl-BINAP, was successfully synthesized and embedded into two different porous organic polymers (Poly-1 and Poly-2). After loading a Rh species, the catalysts were applied for the heterogeneous asymmetric hydroformylation of styrene. Compared with the homogeneous BINAP analogue, the enantioselectivity of Rh/Poly-1 catalyst was drastically increased by approximately 70%. The improved enantioselectivity of the porous Rh/BINAP polymers was attributed to the presence of flexible chiral nanopockets resulting from the increased bulk of the R groups near the catalytic center.