Catalytic Asymmetric Synthesis of Chiral Reagents for Biologically Active Compounds

含光活性膦配体的过渡金属配合物催化的不对称反应因其合成用途而引起了人们的极大兴趣。催化不对称合成研究中最令人兴奋和最具挑战性的课题之一是开发手性配体，使其在催化活性和对映选择性上都能有效地适应给定的反应。我们开发了以2-（二苯基膦）-2′-烷氧基- 1,1′-联萘基（MOPs）为代表的几种新型手性膦配体。轴手性单齿膦配体MOPs是三种新型钯催化不对称反应的有效配体：1)烯烃的不对称硅氢化反应，为制备旋光性醇提供了新的有效途径。2) 1,3 -炔的不对称硼氢化反应得到光学活性的烯基硼烷。3)丙烯基酯与甲酸的不对称还原。我们还对钯催化的不对称Heck型反应、烯丙基氯化物的不对称硅基化反应以及异氰乙酸酯与氟化苯甲醛在手性二茂铁膦金(I)催化剂存在下的不对称醛醇反应进行了机理研究。

Asymmetric reactions catalyzed by transition metal complexes containing optically active phosphine ligands have attracted significant interest for their synthetic utility. One of the most exciting and challenging subjects in research on the catalytic asymmetric synthesis is development of the chiral ligand which will fit in with a given reaction efficientlyin catalytic activity as well as in enantioselectivity. We have dveloped several types of new chiral phosphine ligands represented by 2-(diphenylphosphino)-2'-alkoxy-1, 1'-binaphthyls (MOPs). The axially chiral monodentate phosphine ligands MOPs were found to be efficient ligands for three types of new palladium-catalyzed asymmetric reactions : 1) Asynmmetric hydrosilylation of olefins which provides a new efficient route to optically active alcohols. 2) Asynmmetric hydroboration of 1, 3-enynes giving optically active allenylboranes. 3) Asynmmetric reduction of allylic esters with formic acid.We have also carried out mechanistic studies on palladium-catalyzed asymmetric Heck type reaction, asymmetric silylation of allylic chlorides, and asymmetric aldol reAction of isocyanoacetate with fluorinated benzaldehydes in the presence of chiral ferrocenylphosphine-gold(I) catalyst.