Synthesis of D-(-)-pantolactone via asymmetric hydrogenation assisted by a polyether-functionalized ionic liquid
To solve the problem of recycling difficulty of chiral catalysts in asymmetric hydrogenation,rhodium-catalyzed homogeneous asymmetric hydrogenation of ketopantoyl lactone assisted by a polyether guanidinium ionic liquid was studied based on amino acid-and imidazolium-tagged chiral pyrrolidinodiphosphine ligands.The effects of rhodium precursor,diphosphine ligand structure,solvent effect and polyether ionic liquid doping on the catalytic activity and enantioselectivity were investigated.A homogeneous catalysis-liquid/solid separation system was constructed for the separation and recycling of the chiral catalyst using the optimal diphosphine ligand.The catalytic system showed high catalytic activity,enantioselectivity and long-term stability,and no significant decrease in catalytic performance was observed after 5 runs.This study provides the theoretical and experimental basis for the feasibility of asymmetric hydrogenation synthesis of D-pantolactone.
国家科技期刊平台
NSTL
万方数据
