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1.
不对称Reformatsky反应   总被引:7,自引:0,他引:7  
宓爱巧  张晓梅 《合成化学》1996,4(4):317-324
综述了60年代至今不对称诱导和不对称催化Reformatsky拔应的研究,进展参考文献19篇。  相似文献   

2.
有机不对称放大反应研究进展   总被引:2,自引:0,他引:2  
概述了不对称放大的提出,不对称放大反应类型,不对称放大反应类型,不对称放大反应中关键配合物的以及不对称放大的数学模型。  相似文献   

3.
C2轴不对称联芳香化合物的合成研究进展   总被引:1,自引:0,他引:1  
概述了近年来C2轴不对称联芳香化合物的合成与不对称偶联的研究进展。  相似文献   

4.
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   

5.
李岩云 《分子催化》2011,25(1):90-96
本文介绍了手性铁催化体系在酮及亚胺的不对称还原、烯烃及硫醚的不对称氧化、不对称环加成、不对称环丙烷化以及不对称Friedel-Crafts烷基化等反应中的应用.  相似文献   

6.
手性原子簇合物与不对称催化反应   总被引:3,自引:2,他引:3  
殷元骐 《分子催化》1997,11(6):445-454
以骨架手性原子簇合物为催化剂的不对称催化反应一直认为是极富挑战性的课题,一旦实现,将是一种理想和概念上的突破,回顾原子簇合物的不对性及不对称催化反应的进展,阐述了我们的目标和一些相关的问题。  相似文献   

7.
面包酵母在催化不对称合成中的应用   总被引:8,自引:0,他引:8  
介绍了当前国内外在以面包酵母为催化剂不对称催化合成手性化合物的研究情况,重点介绍了面包酵母催化各类潜手性羰基的不对称还原、潜手性碳一碳双键的不对称加成和碳一碳键形成的反应情况,讨论了各种提高酵母催化不对称合成反应立体选择性的方法,对酵母催化不对称合成有关生物学方面的研究进行了简单的介绍。  相似文献   

8.
猪肝酯酸PLE(Pig Liver Esterase)对双酯具有特殊的不对称水解性,而且可获得高产率和高光学纯的不对称水解产物。本文简要介绍PLE作为一种有效的酶催化剂,在温和的条件下,对双酯的不对称水解反应和在不对称合成中应用的近况。  相似文献   

9.
综述了钯-手性膦配体催化剂在烯烃的不对称氢氰化、不对称羰基化、不对称交叉偶联、不对称氢化硅氢化等方面的研究进展。参考文献36篇。  相似文献   

10.
王宗睦 《化学通报》1992,(10):1-5,25
在不对称合成反应中,使用低光学纯度的手性源物质得到高光学纯度的产物的现象,称为不对称放大。本文以日本的小国和野依两教授的奠基性工作为中心,对于不对称放大的发现、特点和机理以及发展前景,作扼要的介绍。  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.
An efficient approach to the synthesis of highly congested di, penta and hexacyclic pyrazoles as well as imidazole fragment containing novel heterocyclic molecule has been developed through a carbanion induced transformation of suitably functionalized 2H-pyran-2-ones, benzo[h]chromene and thiochromeno[4,3-b]pyrans. Due to the presence of fluorescence, we report their prime application metal sensor as off/on switching in ferric ions.  相似文献   

17.
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   

18.
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   

19.
An efficient tandem approach for the selective synthesis of 4,5-dihydroimidazo[1,5-a]quinoxalines 6ag and imidazo[1,5-a]quinoxalines 7ah by the reaction of 2-imidazolyl anilines 4ac with aryl aldehydes 5ak under mild reaction conditions is described. Introduction of electron releasing alkyl groups in substrates 4ab was found to be instrumental for the success of the reaction.  相似文献   

20.
The Diels-Alder reactivity of 1,2-heteroborines (H4C4B(H)X, X?=?NH, PH, AsH; O, S, Se) has been computationally explored by means of Density Functional Theory (DFT) calculations. The influence of the HB?=?X fragment on the reactivity of the system has been quantitatively analyzed in detail by means of the so-called Activation Strain Model (ASM) of reactivity. It is found that the interaction between these species and the dienophile is significantly stronger than that computed for their all-carbon isoelectronic counterpart, benzene. In addition, the strain energy plays a key role in the observed reactivity trends. The role of the aromaticity strength of these heteroarenes on the reactivity is also assessed.  相似文献   

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