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手性螺环配体的合成及其在不对称催化反应中的应用研究进展 总被引:2,自引:0,他引:2
手性螺环配体的合成及其在不对称催化反应中的应用是不对称合成和催化研究中重要的研究领域之一, 一些手性螺环配体被合成出来并成功地应用于不对称催化反应中. 综述了近十年来手性螺环配体的合成及在不对称催化反应中的应用研究进展. 相似文献
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糖类化合物价廉易得,具有天然手性结构,糖环上的多个羟基经过修饰,可以连接多种官能团。近年来手性糖类化合物的合成与应用研究引起了人们的广泛关注,尤其是在不对称合成和催化中的应用研究已成为有机化学中非常活跃的领域。碳水化合物含磷手性配体在不对称催化反应中的应用研究进展十分迅速,本文综述了近年来碳水化合物含磷手性配体与金属形成络合物作为催化剂,在不对称催化氢化、不对称烯丙位取代和不对称氢甲酰化等反应中的研究进展。 相似文献
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手性金属配合物催化剂在不对称合成中占有重要地位[1-3]。在该类催化剂参与的不对称催化反应中,配合物中手性配体是催化反应立体选择性优劣的关键[4,5]。为了改进该类催化剂的性能,主要对手性配体进行过化学修饰。目前合成的手性催化剂几乎都是由同一种手性配体和一种金属离子组成的二元配合物,且高效者并不多.文献[6]曾提到有关手性三元配合物(亦称手性混合配体配合物)。在不对称催化中应用的可能性,但未见具体报道。本文以中性含氮配体和含氧酸与铜(Ⅱ)配位合成了一类手性三元铜(Ⅱ)配合物及其在不对称合成菊酸中的催化性能。 相似文献
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Chiral ligands play an important role in asymmetric synthesis. Among them the ligands having planar chirality attract more interesting of organic chemists because of their unique structure. Recently, some new types of planar chiral ligands, including 1,1'-disubstituted ferrocene 1, bis(ferrocene carboxylic)diaminocyclohexane 2, and benzylic substituted cyclophane 3, are synthesized (Scheme 1)[1]. These chiral ligands have been successfully used in asymmetric allylic alkylation, Heck reaction, etc. The role of planar chirality in asymmetric induction by using NMR and X-ray are also studied. 相似文献
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Advances in the palladium-catalyzed asymmetric hydrosilylation of 1,3-dienes are presented according to substrate types and chiral monophosphine ligands. Chiral monodentate phosphine ligands with a binaphthyl moiety have been proven to be the most efficient ligands for cyclic 1,3-dienes, and planar chiral ferrocenylmonophosphine ligands with two ferrocenyl moieties for linear 1,3-dienes. The ferrocenylmonophosphine ligands have expanded the substrate scope to 1,3-enynes in the asymmetric hydrosilylation. Palladium-catalyzed asymmetric hydrosilylation of 1,3-dienes and 1,3-enynes leads to the stereoselective synthesis of allylsilanes and allenylsilanes, respectively. 相似文献
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A series of new planar and central chiral ligands based on [2.2]paracyclophane backbones were designed and prepared from enantiomerically pure 4-amino-13-bromo[2.2]paracyclophane and commercially available chiral amino alcohols. Their application in a copper-catalyzed asymmetric Henry reaction resulted in secondary alcohols with high yield and excellent selectivity for active aldehydes (up to 94% ee). This is a successful example of employing planar chiral [2.2]paracyclophane ligands in copper-catalyzed reaction. 相似文献
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Ferrocene with planar chirality are of increasing importance in the synthesis of chiral ligands used in asymmetric catalysis and asymmetric synthesis.[1~3] To prepare Ugi type of chiral base, the most common method is the resolution of rac-N,N-dimethyl- 1-ferrocenylethylamine (1). 相似文献
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Genet C Canipa SJ O'Brien P Taylor S 《Journal of the American Chemical Society》2006,128(29):9336-9337
The catalytic asymmetric synthesis of planar chiral ferrocenes and P-stereogenic phosphines and bisphosphines (important classes of chiral ligands for metal-catalyzed asymmetric processes) is successfully demonstrated using n-BuLi or s-BuLi in combination with substoichiometric quantities (0.1-0.5 equiv) of (-)-sparteine or the (+)-sparteine surrogate. 相似文献
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Fuyan He Yudao Ma Lei Zhao Wenzeng Duan Jianqiang Chen Zhongxi Zhao 《Tetrahedron: Asymmetry》2012,23(11-12):809-817
A series of diastereomerically pure Schiff base ligands based on [2.2]paracyclophane backbones were synthesized and separated. The new planar chiral [2.2]paracyclophane Schiff bases were used as ligands in Cu-catalyzed asymmetric Henry reactions with high yields and enantioselectivities. 相似文献
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New ferrocenylphosphinoimidazolidines containing central chirality and planar chirality were found to act as highly effective chiral ligands in Pd-catalyzed asymmetric allylic alkylation of 1,3-diphenyl-2-propenyl acetate with dimethyl malonate. 相似文献
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Four newly designed CyPHOX ligands with chiral cyclohexane scaffold replacing the previous planar aryl group of PHOX ligands, were efficiently prepared. The synthesis features a kinetically controlled asymmetric phos-Michael reactions of trisubstituted cyclic carboxylates, which is quite simple, reliable and scalable. 相似文献
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Planarly chiral ferrocene derivatives with bridged cyclopentadienyl rings are interesting ligands in asymmetric catalysis. A planar stereogenic unit is conveniently introduced by diastereoselective ortho-lithiation. The directed lithiation of several [5]ferrocenophane derivatives followed by quenching with chlorodiphenylphosphane led to planarly chiral ligands. The sense of diastereoselection was studied by computational methods. Absolute configuration of methoxy phosphane was determined by single crystal X-ray diffraction study. 相似文献
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Wenzeng Duan Yudao Ma Bo Qu Lei Zhao Jianqiang Chen Chun Song 《Tetrahedron: Asymmetry》2012,23(18-19):1369-1375
A series of novel planar chiral alkoxy/sulfonate-substituted carbene precursors have been designed and synthesized. They were used as N-heterocyclic carbene ligands in the Rh-catalyzed asymmetric addition of arylboronic acids to aromatic aldehydes, affording chiral diarylmethanols with high yields and moderate enantioselectivities. 相似文献