手性金属催化剂在不对称环丙烷化反应中的应用进展

手性金属催化剂在不对称环丙烷化反应中的应用一直是不对称合成领域的一个热点。对三十多年来的这一领域的手性金属催化剂的发展作了详细的归纳和评述。     

烯烃不对称催化环丙烷化反应进展评述

本文从手性配体的发展出发, 综述了烯烃不对称环丙烷化反应近10 年来的研究进展, 对半咕啉、双　唑啉等C₂ 轴手性配体在该反应中的应用做了详细论述, 介绍了反应机理研究的最新进展, 并探讨了该反应在走向工业应用过程中所面临的主要问题。     

手性金属配合物催化的不对称环丙烷化反应的新进展

总结了近年来关于环丙烷化反应中各种手性金属催化剂的研究进展, 包括席夫碱、噁唑啉、卟啉、联吡啶及四吡啶、羧酸酯等类型的手性化合物作为配体的金属催化剂.     

不对称氮杂环丙烷化反应的研究

本文综述了近20年来从潜手性烯烃和亚胺出发不对称催化氮杂环丙烷化反应的研究进展,重点评述了手性配体及氮转移试剂(或碳转移试剂)的研究.     

利用不对称催化的环丙烷化反应构建四氢吡咯并吲哚啉骨架

以CuOTf/Ln为催化体系,色胺衍生物与重氮乙酸乙酯于-50℃反应36 h,首次实现了吲哚2,3-位双键的不对称催化环丙烷化反应,构建了四氢吡咯并吲哚啉骨架,收率42%,50%ee,其结构经1H NMR表征.     

一种新型手性席夫碱的合成及其在不对称环丙烷化反应中的催化性能

在不对称催化的发展过程中,设计与合成新的手性配体一直是人们所关注的热点,并已取得很大的进展[1].     

手性铜络合物催化2,5—二甲基—2,4—己二烯不对称环丙烷化反应的研究（Ⅰ）

手性铜络合物催化２，５－二甲基－２，４－己二烯不对称环丙烷化反应的研究（Ⅰ）陈惠麟王胜国郑卓（中国科学院大连化学物理研究所大连１１６０２３）关键词手性铜（Ⅱ）络合物环丙烷化不对称反应分类号Ｏ６４３．３２第一菊酸乙酯［２，２－二甲基－３－（２－甲基丙烯...     

手性联萘胺衍生物为配体的铜络合物催化下某些烯烃的不对称环丙烷化反应

以1,1'-联萘-2,2'-二胺为手性源合成了8对16种光活性铜络合物,考察了它们对1,1-二苯乙烯、苯乙烯和2,5-二甲基-2,4-己二烯等3种烯烃的不对称环丙烷化反应的光学诱导活性.结果表明,以旋光活性联萘胺同水杨醛及2-羟基萘甲醛缩合而得到的Schiff碱为配体的铜络合物的催化效果最佳.催化剂对2,5-二甲基-2,4-己二烯的催化效果优于其它两种烯烃.     

二取代双噁唑啉衍生物的合成及其在不对称环丙烷化反应中的应用

通过双亚氨酯盐酸盐与手性胺醇反应简便地合成了二取代双(口恶)唑啉衍生物,并将其与铜配位运用于重氮醋酸酯对烯烃的不对称环丙化反应,不对称诱导反应光学产物收率最高达95%d.e.     

新型手性双二茂铁希呋碱亚胺配体的合成及其在不对称环丙烷化反应中的应用

以手性二茂铁乙胺为手性前体分别与吡啶二醛和吡啶二酮进行希呋碱缩合反应，合成了两种二茂铁手性亚胺膦配体，并经元素分析，^1HNMR，^31PNMR等手段进行了表征，用这类化合物作为手性配体，研究了其金属Ru(Ⅱ)配合物对苯乙烯与重氮乙酸乙酯的不对称环丙烷反应的催化作用，结果表明该类化合物的Ru(Ⅱ)配合物具有很高的催化活性。     

Tol-BINAP 配体用于金属催化的烯烃不对称环丙烷化反应

以Cu(Tos)2,Cu(ClO4)26H2O,Cu(CH3CN)4ClO4,(CuOTf)2.Ben与tol-BINAP原位形成的Cu-(tol-BI-NAP)配合物催化2,5-二甲基-2,4-己二烯与重氮乙酸酯的不对称环丙烷化反应,催化剂表现出高的反应活性和较低的立体选择性.     

New Chiral Substituted 8-Quinolinyl-oxazolines as Ligands for Copper(I)-catalyzed Asymmetric Cyclopropanation

ＩｎｔｒｏｄｕｃｔｉｏｎＡｓｙｍｍｅｔｒｉｃｃａｔａｌｙｔｉｃｃｙｃｌｏｐｒｏｐａｎａｔｉｏｎｏｆｏｌｅｆｉｎｓｗｉｔｈｄｉａｚｏｃｏｍｐｏｕｎｄｓｉｓｏｎｅｏｆｔｈｅｍｏｓｔｕｓｅｆｕｌｍｅｔｈｏｄｓｆｏｒｔｈｅｓｙｎｔｈｅｓｉｓｏｆｃｈｉｒａｌｃｙｃｌｏｐｒｏｐａｎｅｓ .1Ａｎｕｍｂｅｒｏｆｅｆｆｉｃｉｅｎｔｃｈｉｒａｌｌｉｇａｎｄｓ ,ｐａｒｔｉｃｕｌａｒｌｙｂｉｓｎｉｔｒｏｇｅｎｌｉｇａｎｄｓ ,ｈａｖｅｂｅｅｎｄｅｖｅｌｏｐｅｄ ,ａｎｄｅｘｃｅｌｌｅｎｔｅｎａｎｔｉｏｓｅｌｅｃｔｉｖｉｔｉ…     

手性双(口恶)唑啉配体-金属配合物在催化不对称环丙烷化反应中的应用研究进展

将用于催化不对称环丙烷化反应中的手性双(口恶)唑啉配体按相应羧酸母体骨架分为丙二酸类,酒石酸类,吡啶二羧酸类,联苯、联萘及双核二茂铁类,将聚合物支载的双(口恶)唑啉配体单独进行了讨论.对各类配体的最新研究进展及其金属配合物在不对称环丙烷化反应中的应用作了总结.     

Asymmetric Sulfonium Ylide Mediated Cyclopropanation: Stereocontrolled Synthesis of (+)‐LY354740

The reaction of ester‐stabilized sulfonium ylides with cyclopentenone to give (+)‐ 5 ((1S,5R,6S)‐ethyl 2‐oxobicyclo[3.1.0]hexane‐6‐carboxylate), an important precursor to the pharmacologically important compound (+)‐LY354740, has been studied using chiral sulfides operating in both catalytic (sulfide, Cu(acac)₂, ethyl diazoacetate, 60 °C) and stoichiometric modes (sulfonium salt, base, room temperature). It was found that the reaction conditions employed had a major influence over both diastereo‐ and enantioselectivity. Under catalytic conditions, good enantioselectivity with low diastereoselectivity was observed, but under stoichiometric conditions low enantioselectivity with high diastereoselectivity was observed. When the stoichiometric reactions were conducted at high dilution, diastereoselectivity was reduced. This indicated that base‐mediated betaine equilibration was occurring (which is slow relative to ring closure at high dilution). Based on this model, conditions for achieving high enantioselectivity were established as follows: use of a preformed ylide, absence of base, hindered ester (to reduce ylide‐mediated betaine equilibration), and low concentration. Under these conditions high enantioselectivity (95 % ee) was achieved, albeit with low diastereocontrol. Our model for selectivity has been applied to other sulfonium ylide mediated cyclopropanation reactions and successfully accounts for the diastereoselectivity observed in all such reported reactions to date.     

Design and Synthesis of Novel Chiral Dirhodium(II) Carboxylate Complexes for Asymmetric Cyclopropanation Reactions

A novel approach to the design of dirhodium(II) tetracarboxylates derived from (S)‐amino acid ligands is reported. The approach is founded on tailoring the steric influences of the overall catalyst structure by reducing the local symmetry of the ligand's N‐heterocyclic tether. The application of the new approach has led to the uncovering of [Rh₂(S‐^tertPTTL)₄] as a new member of the dirhodium(II) family with extraordinary selectivity in cyclopropanation reactions. The stereoselectivity of [Rh₂(S‐^tertPTTL)₄] was found to be comparable to that of [Rh₂(S‐PTAD)₄] (up to >99 % ee), with the extra benefit of being more synthetically accessible. Correlations based on X‐ray structures to justify the observed enantioinduction are also discussed.