共查询到19条相似文献,搜索用时 109 毫秒
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不对称η3-取代反应在有机合成及转化中具有重要的地位,广泛应用于天然产物及药物分子合成中.利用钯催化实现不饱和烃的不对称氢官能团化反应,因其广泛的底物普适性、高的原子经济性和立体选择性控制效果而受到诸多关注,也成为近年来该领域研究的热点.其中,相对于联烯和炔烃底物来说,钯催化的二烯和烯炔的不对称氢官能团化反应研究尚少,近年来才开始快速发展,实现了许多重要突破,并逐步发展成为一类具有高合成价值的策略.本文主要综述了自2020年以来该领域的最新研究进展,从共轭二烯、远程二烯及共轭烯炔等类型的底物出发,总结和概述了相关的研究现状、策略应用和反应机理. 相似文献
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报道了手性膦烯配体在金属铑催化的芳基硼酸对β-芳基-α,β-不饱和磺酸酯不对称共轭加成中的应用.经过系统的反应条件筛选和配体结构优化,发现含手性1,1'-联-2-萘酚骨架的膦烯配体L7与Rh(I)形成的催化剂可以高对映选择性地实现β-芳基-α,β-不饱和磺酸酯化合物的不对称1,4-加成反应.此反应体系条件温和,底物普适性广,并取得了较高的收率(up to 95%)和优秀的对映选择性(up to 99%ee),为合成手性偕二芳基取代的磺酸酯类化合物提供了一种新方法. 相似文献
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Palladacycle Catalyzed Asymmetric PH Addition of Diarylphosphines to N‐Enoyl Phthalimides 下载免费PDF全文
Renta Jonathan Chew Dr. Yunpeng Lu Yu‐Xiang Jia Bin‐Bin Li Esther Hui Yen Wong Rosanne Goh Dr. Yongxin Li Dr. Yinhua Huang Dr. Sumod Appukuttan Pullarkat Prof. Dr. Pak‐Hing Leung 《Chemistry (Weinheim an der Bergstrasse, Germany)》2014,20(44):14514-14517
The first asymmetric phospha‐Michael addition of diarylphosphines to N‐enoyl phthalimides has been developed in the presence of a chiral palladacycle catalyst. A library of free chiral tertiary phosphine adducts were directly obtained with excellent yields and enantioselectivities. Products can be subsequently functionalized to afford β‐phosphinoamides, the direct preparation of which from cinnamides has been notoriously challenging. 相似文献
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Yosuke Sato Chihiro Takagi Prof. Dr. Ryo Shintani Prof. Dr. Kyoko Nozaki 《Angewandte Chemie (International ed. in English)》2017,56(31):9211-9216
A palladium-catalyzed asymmetric synthesis of silicon-stereogenic 5,10-dihydrophenazasilines was developed that proceeds via an unprecedented enantioselective 1,5-palladium migration. High enantioselectivity was achieved by employing 4,4′-bis(trimethylsilyl) (R)-Binap as the chiral ligand, and a series of mechanistic investigations were carried out to probe the catalytic cycle of this process. 相似文献
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Biming Mao Honglei Liu Zhengyang Yan Yi Xu Jiaqing Xu Wei Wang Yongjun Wu Prof. Dr. Hongchao Guo 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2020,132(28):11412-11416
A palladium-catalyzed asymmetric [4+2] cycloaddition of 2-methylidenetrimethylene carbonate with alkenes derived from pyrazolones, indandione, or barbiturate has been successfully developed, affording pharmacologically interesting chiral tetrahydropyran-fused spirocyclic scaffolds. The target compounds were generated in good to excellent yields and with high enantioselectivity (up to 99 % ee). Furthermore, this cycloaddition reaction could be efficiently scaled up, and several synthetic transformations were accomplished for the construction of other useful chiral spiropyrazolone and spiroindandione derivatives. 相似文献
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Miao-Miao Li Qin Xiong Bao-Le Qu Yu-Qing Xiao Prof. Yu Lan Prof. Liang-Qiu Lu Prof. Wen-Jing Xiao 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2020,132(40):17582-17587
Vinylcyclopropanes (VCPs) are commonly used in transition-metal-catalyzed cycloadditions, and the utilization of their recently realized reactivities to construct new cyclic architectures is of great significance in modern synthetic chemistry. Herein, a palladium-catalyzed, visible-light-driven, asymmetric [5+2] cycloaddition of VCPs with α-diazoketones is accomplished by switching the reactivity of the Pd-containing dipolar intermediate from an all-carbon 1,3-dipole to an oxo-1,5-dipole. Enantioenriched seven-membered lactones were produced with good reaction efficiencies and selectivities (23 examples, 52–92 % yields with up to 99:1 er and 12.5:1 dr). In addition, computational investigations were performed to rationalize the observed high chemo- and periselectivities. 相似文献
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