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1.
张占辉 《有机化学》2005,25(4):355-363
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   

2.
李小永  王丽琼  聂进 《有机化学》2004,24(10):1159-1167
三氟甲基磺酸铜[Cu(OTf)2]与各种手性磷氮配体络合催化不对称合成已取得了巨大进展.详细评述了近五年来该类手性铜催化剂在各种不对称催化反应中的最新应用.  相似文献   

3.
三氟甲基磺酸铜 [Cu(OTf) 2 ]与各种手性磷氮配体络合催化不对称合成已取得了巨大进展 .详细评述了近五年来该类手性铜催化剂在各种不对称催化反应中的最新应用  相似文献   

4.
膦-噁唑啉配体形成的催化剂具有出色的催化活性和对映选择性, 被广泛应用于各种不对称催化反应中. 具有面手性的膦-噁唑啉配体是其中重要的一类. 综述了面手性二芳基膦-噁唑啉配体的开发, 并按反应类型介绍了它们在不对称催化反应中的应用.  相似文献   

5.
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   

6.
侯传金  刘小宁  夏英  胡向平 《有机化学》2012,32(12):2239-2247
非对称杂化的手性膦-亚磷酰胺酯配体因其合成简便、易于调控、结构稳定等优点,被广泛应用于不对称催化反应中,如:不对称氢化、不对称氢甲酰化、不对称烯丙基烷基化、不对称氢膦酰化、不对称[3+2]-环加成、不对称1,4-加成和1,4-还原反应等.综述了手性膦-亚磷酰胺酯配体的种类、合成及其在不对称催化反应中的应用.  相似文献   

7.
巫循伟  孙威  侯雪龙 《有机化学》2003,23(9):906-913
[2.2]对环芳烷类平面手性配体在不对称催化反应中的应用近年来引起化学家 们的较大关注。综述了这类手性配体在不对称催化反应中的应用。  相似文献   

8.
发展高效实用的不对称催化反应对手性药物的简洁合成具有重要的意义,而手性配体和催化剂对于发展高效的不对称催化反应尤为关键.综述了基于苯并氧杂膦烷结构的P-手性单膦和双膦配体的设计理念以及它们在手性药物合成中的应用.这类配体具有P-手性、刚性,大位阻和富电子等结构特征,物理化学性质稳定,并且易于衍生化,在过渡金属催化的不对称氢化、偶联、环化和加成反应中表现出优异的催化性能.这些不对称催化反应的发展促进了一系列重要药物分子的高效不对称合成.  相似文献   

9.
手性膦配体的合成及其在不对称催化反应中的应用一直是不对称有机合成和催 化研究中非常重要的研究领域,大量的单齿、双齿和多齿磷配体被合成出来并成功 地应用于不对称催化研究。综述了近十几年来手性磷配体的研究进展。  相似文献   

10.
谢建华  周其林 《化学学报》2014,72(7):778-797
过渡金属参与的不对称催化反应是有机合成化学研究的前沿和热点. 寻找和发现新颖配体骨架并开展新型高效的手性配体及催化剂的设计合成是不对称催化反应研究的核心内容. 从20世纪90年代,特别是进入21世纪以来,螺环骨架手性配体受到了广泛的关注,并逐渐发展成为特色鲜明的手性配体类别. 手性螺环配体的骨架已由多手性的螺[4.4]壬烷骨架发展到只具有单一手性的螺二氢茚和螺[4.4]壬二烯等螺环骨架类型,形成了包括手性螺环单磷配体、双膦配体、膦氮配体、双氮配体等丰富的手性配体库. 这些手性螺环配体及其催化剂不仅在不对称催化氢化、不对称碳―碳键形成、不对称碳―杂原子键形成等多种类型的不对称催化反应中均表现出优异的催化活性和对映选择性,且使得许多原先难以控制对映选择性的不对称催化反应变得可能. 而今,手性螺环结构已成为“优势结构”,相应的手性螺环配体及其催化剂已被国内外同行广泛采用. 手性螺环配体的兴起为手性催化剂研究增加了活力,极大地促进了不对称合成化学的发展. 今后,手性螺环配体的研究除了将向新型、高效、高选择性手性配体及催化剂方向发展外,将其应用于新的不对称催化反应的对映选择性控制、以及应用于手性天然产物和药物的高效不对称合成将成为新的研究热点.  相似文献   

11.
《Tetrahedron: Asymmetry》2006,17(4):642-657
A library of new fine-tunable monodentate phosphite and phosphoramidite ligands based on chiral biphenol have been designed and developed. These monodentate phosphorus ligands have exhibited excellent enantioselectivity in the Pd-catalyzed asymmetric allylic alkylation and Rh-catalyzed asymmetric hydrogenation.  相似文献   

12.
江志东  孟昭海 《中国化学》2007,25(4):542-545
A new and simple method for immobilization of monodentate chiral ligand on the cheap resin has been developed. A series of resin-immobilized phosphoramidite ligands based on BINOL and TADDOL backbones have been synthesized and characterized with gel-phase NMR. The immobilized ligands have been applied to the Pd-catalyzed asymmetric allylic alkylation of 1,3-diphenyl-2-propenyl acetate. Among four ligands, the supported bulky monodentate phosphoramidite ligand based on TADDOL backbone afforded the chiral product with ee up to 65%; moreover, this ligand could be recycled for 3 times without substantial decrease of the conversion and ee.  相似文献   

13.
The design of new chiral ligands is the key in the development of transition metal catalyzed asymmetric synthesis. Many chiral diphosphine ligands have been prepared and applied in asymmetric catalytic reactions with excellent enantioselectivities. Among the chiral diphosphine ligands that have been reported, the atropisomeric C2-symmetric phosphines with a biaryl scaffold initiated by Noyori and co-workers with BINAP were found to have the widest application in the transition metal catalyze…  相似文献   

14.
Reported here is the development of a class of chiral spirosilabiindane scaffolds by Rh‐catalyzed asymmetric double hydrosilation, for the first time. Enantiopure SPSiOL (spirosilabiindane diol), a new type of chiral building block for the preparation of various chiral ligands and catalysts, was readily prepared on greater than 10 gram scale using this protocol. The potential of this new spirosilabiindane scaffold in asymmetric catalysis was preliminarily demonstrated by development of the corresponding monodentate phosphoramidite ligands (SPSiPhos), which were used in both a Rh‐catalyzed hydrogenation and a Pd‐catalyzed intramolecular carboamination.  相似文献   

15.
Choi H  Hua Z  Ojima I 《Organic letters》2004,6(16):2689-2691
Copper-catalyzed asymmetric conjugate addition of diethylzinc to nitroalkenes using new chiral monodentate phosphoramidite ligands proceeds with high enantioselectivity up to 99% ee. [reaction: see text]  相似文献   

16.
报道了一例手性螺环亚磷酰胺配体和镍的络合物催化的硅基保护烯丙醇的不对称烯氢化反应,以较高的收率(最高达97%)和对映选择性(最高达95%ee)合成了一系列含有手性季碳中心的高烯丙醇.该反应为含有手性季碳中心的双官能团化合物的合成提供了新的有效方法.  相似文献   

17.
A palladium-catalyzed asymmetric allylation of isatins with allylic alcohols as an allyl donor was developed by using chiral spiro phosphoramidite ligands. A variety of chiral tertiary homoallylic alcohols 3-allyl-3-hydroxy-2-oxindoles were prepared directly from allylic alcohols in one step with excellent yields and moderate enantioselectivities. This represents the first catalytic asymmetric allylation of ketones with allylic alcohol as the allylating agent.  相似文献   

18.
为了进一步拓展具有螺二氢茚骨架的亚磷酸酰胺酯、亚磷酸酯、亚膦酸酯等手性螺环单磷配体在不对称反应中的应用范围, 研究了手性螺环单磷配体在铑催化苯乙烯衍生物的氢甲酰化反应中的选择性.  相似文献   

19.
A library of 19 chiral tropos phosphorus ligands, based on a flexible (tropos) biphenol unit and a chiral P-bound alcohol (11 phosphites) or secondary amine (8 phosphoramidites), was synthesized. These ligands were screened, individually and as a combination of two, in the rhodium-catalyzed asymmetric hydrogenation of dehydro-alpha-amino acids, dehydro-beta-amino acids, enamides and dimethyl itaconate. ee values up to 98% were obtained for the dehydro-alpha-amino acids, by using the best combination of ligands, a phosphite [4-P(O)2O] and a phosphoramidite [13-P(O)2N]. Kinetic studies of the reactions with the single ligands and with the combination of phosphite [4-P(O)2O] and phosphoramidite [13-P(O)2N] have shown that the phosphite, despite being less enantioselective, promotes the hydrogenation of methyl 2-acetamidoacrylate and methyl 2-acetamidocinnamate faster than the mixture of the same phosphite with the phosphoramidite, while the phosphoramidite alone is much less active. In this way, the reaction was optimized by lowering the phosphite/phosphoramidite ratio (the best ratio is 0.25 equiv phosphite/1.75 equiv phosphoramidite) with a resulting improvement of the product enantiomeric excess. A simple mathematical model for a better understanding of the variation of the enantiomeric excess with the phosphite/phosphoramidite ratio is also presented.  相似文献   

20.
The axially chiral BICOL backbone was functionalised with two third generation carbosilane dendritic wedges and further elaborated to a phosphoramidite ligand. High enantioselectivities were obtained when these monodentate ligands were applied in the rhodium-catalysed asymmetric hydrogenation of methyl 2-acetamidocinnamate.  相似文献   

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