【作者】 张翔；

【导师】 孙立成； 吕小兵；

【作者基本信息】 大连理工大学 ， 应用化学， 2008， 博士

【摘要】 手性Salen配体是近年来不对称催化合成反应中最重要的配体之一,被广泛地应用于末端环氧化物的水解动力学拆分、环氧化合物的不对称开环、不对称环丙烷化反应、杂原子Diels-Alder反应、硫醚不对称氧化反应、烯烃不对称环氧化以及环氧烷烃与CO₂的环加成或共聚等各类反应中。本论文在手性双功能吡咯烷Salen金属配合物的设计合成基础上,考察了SalenCr配合物催化CO₂和环氧烷烃不对称环加成反应以及SalenMn配合物催化非官能化烯烃不对称环氧化反应的催化性能。主要研究工作如下:一、含有亲电-亲核双中心SalenCr配合物的合成及其在CO₂和环氧烷烃环加成反应中的催化性能研究针对亲电和亲核试剂组成的双组分催化体系在CO₂与环氧烷烃的环加成反应过程中存在的浓度效应,论文利用吡咯烷仲胺N上的活泼H,通过1,10-二溴癸烷作为连接“桥梁”,引入大位阻有机碱或者季铵盐,成功地合成了既有亲电中心又有亲核中心的手性双功能吡咯烷SalenCr配合物,通过分子内的协同催化作用,使催化活性对催化剂浓度的依赖得以消除,实现在低催化剂浓度下高效催化CO₂与环氧烷烃的环加成反应。在常温、低压（0.5 MPa）和低的催化剂浓度（[环氧烷烃]/[催化剂]=50000,摩尔比）,不加任何助催化剂的条件下,能有效地催化CO₂和端位环氧烷烃的环加成反应。二、手性吡咯烷SalenMn（Ⅲ）配合物的合成及其在非官能化烯烃不对称环氧化反应中的催化性能研究手性SalenMn（Ⅲ）配合物被认为是迄今为止所发现的催化非官能化烯烃的不对称环氧化反应最有效的催化剂之一。在NaClO水/有机两相氧化体系中,对共轭顺式二取代或环状烯烃的不对称环氧化具有高的对映体选择性,然而,即使加入昂贵的吡啶的氮氧化物,环氧化反应也通常需要长的反应时间。论文利用吡咯烷仲胺N上的活泼H,引入咪唑或者季铵盐,合成了手性双功能SalenMn（Ⅲ）配合物Mn-1～Mn-3。分子内含有咪唑基团的双功能配合物Mn-1,即使不加任何助催化剂条件下,也能有效地催化取代色烯的不对称环氧化反应,获得高的环氧化产率（＞88%）和对映体选择性（＞82%）。分子内季铵盐的双功能配合物Mn-2和Mn-3,具有分子内的相转移能力,大大提高了环氧化反应的速率,比Jacobsen催化剂所需的反应时间缩短了一半,而且得到高的环氧化产率（＞91%）和高对映体选择性（＞88%）。更多还原

【Abstract】 The chiral Salen ligand,one of most important ligands for asymmetric catalytic reaction, has been widely applied in hydrolytic kinetic resolution of racemic epoxides,asymmetric ring-opening of epoxides,asymmetric cyclopropanation reaction,Diels-Alder reaction, asymmetric oxidation of sulfides,asymmetric epoxidation of unfunctionalized alkenes,as well as cycloaddition or copolymerization of CO₂ and epoxides.In this thesis,chiral metal-salen complexes with an anchored functionl group on its pyrrolidine ring were synthesized and applied to the asymmetric cycloaddition of CO₂ and epoxides and epoxidation of unfunctionalized alkenes.1.Synthesis of chiral（pyrrolidine salen）Cr（Ⅲ） complexes containing an electrophilic and nucleophilic center in one molecule and their catalytic properties for asymmetric cycloaddition of CO₂ and epoxides.The binary catalyst system,consisting of the chiral SalenM（Ⅲ） complex as the electrophlie and quaternary ammonium salt or sterically hindered strong base as the nucleophile,can effectively catalyze the cycloaddition of CO₂ and epoxides at mild conditions. However,the reaction rate was dependent on the catalyst concentration,and nearly complete loss in activity was observed at a high[epoxide]/[catalyst]ratio.As a result,a catalyst containing an electrophilic center[（pyrrolidine salen）Cr（Ⅲ）]and a sterically hindered base or quaternary ammonium salt in one molecule,which was linked with 1,10-dibromodecane,was synthesized and applied to the cycloaddition of CO₂ and epoxides. With the intramolecular two-centers cooperation catalysis,the catalyst concentration had negligible influence on the reaction rate.At a condition of[PO]/[catalyst]ratio of 50000,25℃and 0.5 MPa pressure,the functional catalyst could effectively catalyze the cycloaddition of CO₂ and epoxides in the absence of any cocatalyst.2.Synthesis of bifunctional chiral（pyrrolidine salen）Mn（Ⅲ） complexes and their catalytic performance for asymmetric epoxidation of unfunctionalized alkenes enantioselectivity of epoxidationIt’s well known that chiral SalenMn（Ⅲ） complexes are effective catalysts for the asymmetric epoxidation of unfunctionalized alkenes.Although high product was observed in the epoxidation of non-functionalised cis or cyclic alkenes using NaOCl as oxidant under biphasic systems,a prolong reaction time is seem to be prerequisite for obtaining high yield even in the presence of the expensive pyridine N-oxide as cocatalyst.In this thesis,a catalytic system based on the chiral pyrrolidine SalenMn（Ⅲ） complexes Mn-1～Mn-3 with an anchored functional group,linked by a 1,10-dibromodecane bridge,was synthesized and used for the asymmetric epoxidation of substituted chromenes with NaClO/PPNO as oxidant system in the aqueous/organic biphasic medium.The SalenMn（Ⅲ） complex 1,bearing an imidazole group at the N_aza-substituent in the pyrrolidine backbone,showed high activity and enantioselectivity in the absence of any cocatalyst,while SalenMn（Ⅲ） complexes 2 and 3 with an anchored internal quaternary ammonium salts could increase the epoxidation reaction rate and displayed significantly high activity owing to the phase transfer capability of the intramolecular quaternary ammonium salt unit of the SalenMn（Ⅲ） catalyst.更多还原