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1.
近年研究表明二茂铁的环钯化衍生物被广泛地应用于各类偶联反应中,比如Heck反应、Suzuki反应、aza-Claisen重排反应等.主要综述了含氮导向基的二茂铁衍生物的环钯化反应,包括通过不对称诱导或拆分手段合成具有平面手性环钯化合物,基于环金属化反应1,1'-取代二茂铁钯化物的合成,以及其在催化反应的应用.  相似文献   

2.
在不对称催化反应中,平面手性二茂铁化合物是一类非常高效的手性配体和催化剂.从原子和步骤经济性方面考虑,与传统方法相比不对称碳氢键直接官能团化反应是构建平面手性二茂铁最简洁有效的方法.综述了铜、钯、铑、铱、金和铂等过渡金属催化的不对称碳氢键官能团化反应合成平面手性二茂铁化合物的最新进展.此外,还介绍了利用这些方法合成多种平面手性二茂铁配体和催化剂及其不对称催化反应.  相似文献   

3.
1-和1,1''-取代的手性二茂铁Schiff碱的合成及表征   总被引:3,自引:0,他引:3  
在过去十年中,二茂铁化学不断地发展,丰富,特别是在材料化学,电化学,不对称合成化学中引起了人们的极大兴趣,其应用前景也愈来愈被看好。其中,二茂铁的Schiff碱是重要的一类衍生物,可方便地进行环钯化反应和C=N双键的加成反应,合成具有良好的光电性能和催化作用的金属有机化合物,所以其发展已受到人们的关注[1]。目前,对它的研究多集中在非手性的衍生物上,通过它们合成高光学纯度的金属有机化合物(如:具有平面手性的环钯化合物等)往往要用具有光学活性的化合物进行拆分[2],方法复杂,不易操作。我们设想,合成带有手性的二茂铁Sch…  相似文献   

4.
通过手性二茂铁亚胺环钯化合物(Sp,Sp)-[{Pd[(η^5-C~5H~5)Fe{(η^5-C~5H~3)C(CH~3)=N-Ar}](μ-Cl)}~2],手性二茂铁亚胺环汞化合物[HgCl{η^5-C~5H~5)Fe(η^5-C~5H~3)C(CH~3)=N-Ar}]与金属锡的金属转移反应,均得到保持茂环平面手性的手性二茂铁亚胺环锡化合物。产物均经元素分析、IR和^1HNMR鉴定,X射线晶体结构分析确定了有机锡化合物的绝对构型,并经CD谱验证。  相似文献   

5.
Khan Ijaz  李红芳  吴学  张勇健 《化学学报》2018,76(11):874-877
利用金属钯与非手性膦配体原位生成的钯配合物和手性方酰胺为协同催化体系实现了乙烯基碳酸乙烯酯(VECs)与甲醛的不对称脱羧环加成反应,以良好的产率和对映选择性得到了手性叔醇类化合物.发现了有机小分子催化剂-手性方酰胺可实现该反应的不对称诱导,为通过两性离子烯丙基钯中间体的环加成反应的研究提供了新的思路.  相似文献   

6.
崔坤  李公强  夏纪宝 《有机化学》2022,(5):1567-1568
<正>手性有机磷化合物在不对称金属和有机小分子催化以及手性医药材料研究等领域有着广泛的应用,尤其在不对称催化反应中,手性膦配体发挥着重要作用.传统制备手性有机磷化合物的方法经常从化学计量的手性助剂出发,或通过手性拆分外消旋有机磷化合物.近年来随着不对称催化的快速发展,通过一系列高效的不对称催化反应可以构建手性有机磷化合物,  相似文献   

7.
报道了钯催化的分子内不对称C—H键芳基化反应.以简单易得的二茂铁羰基化合物为底物,Pd(CH_3CN)_4(OTf)_2为催化剂,使用手性磷酸作为唯一手性源,Buchwald类型联苯单膦配体,甲苯作溶剂,100℃进行反应,得到一系列二茂铁化合物,ee值最高可达83%.该反应为合成平面手性二茂铁化合物提供了一种新途径.  相似文献   

8.
手性二茂金属膦配体在不对称合成中的应用及新进展   总被引:1,自引:0,他引:1  
牟宗刚  吕士杰 《分子催化》1996,10(2):149-159
手性二茂金属膦配体在不对称合成中的应用及新进展牟宗刚,吕士杰,周宏英,傅宏祥(中国科学院兰州化学物理研究所兰州730000)关键词二茂铁膦配体,烯丙基化合物,二茂钌膦配体,不对称合成,不对称催化,均相催化1前言众所周知,催化作用的研究已成为近代化学的...  相似文献   

9.
亮点介绍     
<正>钯催化不对称碳氢键活化构建磷手性中心化合物Angew.Chem.Int.Ed.2015,54,6265~6269含磷手性中心化合物可被用来合成手性膦配体在不对称催化反应中应用,但通常其合成会涉及到拆分或手性柱分离等过程.中国科学院上海有机化学研究所段伟良等对二芳基磷酰溴代苯胺的分子内碳氢活化反应进行了探索,尝试构建含磷手性中心化合物.发现钯催化剂结合酒石酸衍生的亚膦酰胺配体,可以选择性地切断磷上一个芳基的  相似文献   

10.
平面手性二茂铁衍生物已经发展成为不对称催化反应中一类良好的手性配体和手性催化剂.高效、高对映选择性的平面手性二茂铁衍生物合成方法研究是不对称催化研究的热点之一.综述了近年来利用过渡金属催化法合成面手性二茂铁衍生物的进展.  相似文献   

11.
A new and simple synthesis of novel N-protected methyl 5-substituted-4-hydroxypyrrole-3-carboxylates, which exist in equilibrium with their 4-oxo tautomers, has been developed in two steps starting from N-protected α-amino acids. The key intermediates are enaminones, which can also be isolated, characterized, and used for the construction of other functionalized heterocycles, before they spontaneously decompose to pyrrole products. 4-Hydroxypyrroles are prone to partial aerial oxidation but can be efficiently alkylated or reduced to stable polysubstituted pyrrolidine derivatives.  相似文献   

12.
The chemoselectivity in the intramolecular CH insertion of various diazosulfonamides has been experimentally studied. The results reveal that the aliphatic 1,4-, 1,5-, or 1,6-C(sp3)?H insertions of diazosulfonamides are not accessible, while the aromatic 1,5-C(sp2)?H insertion can be realized specifically by adjusting the diazo-adjacent group. In addition, the general chemoselectivities in the intramolecular CH insertions of diazosulfonyl compounds are summarized. Generally, diazosulfones undergo both aromatic 1,5-C(sp2)?H and aliphatic 1,5- and 1,6-C(sp3)?H insertions, while diazosulfonates undergo aliphatic 1,5- and 1,6-C(sp3)?H insertions. However, diazosulfonamides only undergo aromatic 1,5-C(sp2)?H insertion.  相似文献   

13.
N-Heterocyclic carbene-palladacyclic complexes 3 were successfully achieved in a one-pot procedure under mild conditions. The structure of 3a was unambiguously confirmed by X-ray single crystal diffraction and it was an active catalyst in the Buchwald-Hartwig amination and α-arylation of ketones even at very low catalyst loadings (0.01?mol%).  相似文献   

14.
An efficient iodine-mediated oxidative Pictet-Spengler reaction in dimethyl sulphoxide (DMSO) using terminal alkynes as the 2-oxoaldehyde surrogate for the synthesis of aryl (9H-pyrido[3,4-b]indol-1-yl)methanones is described. The scope of the protocol includes the total synthesis of Fascaplysin, Eudistomins Y1 and Y2. The methodology is extended for preparing pyrrolo[1,2-a]-quinoxaline and indolo[1,5-a]quinoxaline derivatives. The utility of 1-aroyl-β-carbolines was demonstrated by performing palladium-catalyzed β-carboline directed ortho-C(sp2)-H functionalization of the phenyl ring with thiomethyl (SMe) group using DMSO as source and for accessing 4-aryl-canthin-6-ones.  相似文献   

15.
In this Letter, we described a facile method for constructing fused bicyclic 1-arylpyrazol-5-one ring system. We employed various methylene-containing carboxylic acids as the substrates and proved that the pyrazolone ring closure requires activated methylene group in intermediate II. Accordingly, a series of structurally diversified, fused bicyclic 1-arylpyrazol-5-ones was prepared in moderate to high yields using the requisite substrates.  相似文献   

16.
Synthesis of substituted pyrrolo[1,2-a]pyrazines and pyrazino[1,2-a]indoles from the Morita-Baylis-Hillman derivatives of acrylates via saponification followed by Curtius reaction is described.  相似文献   

17.
用正丁胺作为碳源,采用射频辉光放电制备碳膜,选用激光染料R6G和聚乙二醇混合液作为蒸气源,采用单源热蒸发,在蒸发室与染料同时沉积得到混合膜,用拉曼光谱和红外光谱分析了碳膜的结构和键合方式,分析表明:碳膜中存在胺基团和氢原子.混合膜的荧光谱测量结果表明,认为正丁胺对染料荧光谱的影响是因为胺基和氢原子的存在.  相似文献   

18.
19.
A series of 20 CuAIAC reactions between eight 4-acylamino substituted pyrazolidine-3-one-1-azomethine imines and four terminal ynones were performed using Cu0 as catalyst. The corresponding fluorescent cycloadducts were obtained in very high yields upon simple workup. Thus, Cu-metal turned out to be a better catalyst than CuI in terms of yield and ease of isolation. Availability of azomethine imines, mild reaction conditions, and simple workup enable a “click” access to libraries of densely substituted 2,3-dihydro-1H,5H-pyrazolo[1,2-a]pyrazol-1-ones. Reactivity of differently substituted dipoles was evaluated experimentally and by quantum chemical methods (DFT).  相似文献   

20.
(E)-4-(Fullerenopyrrolidin-1-yl)-3-methylbut-2-enoic acid and its corresponding succinimidyl ester, readily obtained through Prato-type modification of C60, were used for the selective N-acylation of polyamines. The thus obtained conjugates were evaluated for their antioxidative and anti-inflammatory activity and their cytotoxicity was determined. Members of this family of compounds showed interesting anti-lipid peroxidation, anti-lipoxygenase and anti-inflammatory activity and comparable cytocompatibility to spermidine.  相似文献   

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