Synthesis And Application Of Chiral Phosphors-olefin Hybrid Ligands Derived From L-proline

The chiral olefins phosphine ligands have become a hot research topic and aswell as an important ligand since the first olefins phosphine ligands was reported in2004. Compared with the conventional olefins ligands and phosphine ligands,olefins phosphine ligands exhibit better catalytic activity and stereoselectivitybecause they can not only take advantages of high coordination ability of phosphinbut also make use of chiral environment of olefins..In our research, nine different structures of olefins phosphine ligands withproline as the matrix material have been synthesized by using economical L-proline.The1,4-addition reactions between phenylboronic acid and cyclohexennone werecatalyzed by the complexation between the chiral olefins phosphine ligands andrhodium, which showed that the ligands possessed high catalytic activity andstereoselectivity. When the reaction was catalyzed by the optimal structure ofligands, the conversion was99%, and the selectivity was86%ee. The asymmetric1,4-addition reactions between phenylboronic acid and cyclohexennone, orcyclopetenone, and or α,β-unsaturated ketone were catalyzed by the complexationbetween the optimal chiral olefins phosphine ligands and rhodium. Under optimumexperimental condition, rhodium, KOH,1,4-dioxane was used as a catalyst, alkaliand solvent respectively, and the reaction temperature was70℃. The reaction witha conversion of95%-99%and a selectivity of60%ee-85%ee, exhibited bettercatalytic activity and stereoselectivity, which showed that the synthesized ligandscould be applied widely.Both the synthesized ligands and the additive products were characterized byNMR and HRMS, and the intermediates and products with optical configurationwere characterized by specific rotation and ee value.