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Gaoyuan Ma Prof. Dr. Mukund P. Sibi 《Chemistry (Weinheim an der Bergstrasse, Germany)》2015,21(33):11644-11657
Biaryl compounds with axial chirality are very common in synthetic chemistry, especially in catalysis. Axially chiral biaryls are important due to their biological activities and extensive applications in asymmetric catalysis. Thus the development of efficient enantioselective methods for their synthesis has attracted considerable attention. This Minireview discusses the progress made in catalytic kinetic resolution of biaryl compounds and chronicles significant advances made recently in catalytic kinetic resolution of biaryl scaffolds. 相似文献
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Jing Zhang Meng Liu Chuanhua Wu Gaoyuan Zhao Peiqi Chen Lin Zhou Xingang Xie Ran Fang Huilin Li Xuegong She 《Angewandte Chemie (International ed. in English)》2020,59(10):3966-3970
The first total synthesis of the Euphorbia diterpenoid pepluanol B in both racemic and enantioenriched form involves 20 steps from a known bicyclic diol. This synthesis features an unprecedented bromo‐epoxidation to control the eight‐membered‐ring conformation. In addition, salient reactions for the construction of the tetracyclic backbone include a sterically challenging aldol reaction to establish the quaternary center, a ring closing metathesis (RCM) to forge the eight‐membered ring, and a diastereoselective cyclopropanation to assemble the embedded cyclopropane motif. 相似文献
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Zhuliang Zhong Donghui Ma Gaoyuan Zhao Huilin Li Dengyu Xu Dr. Xingang Xie Prof. Dr. Xuegong She 《化学:亚洲杂志》2015,10(12):2599-2603
The first asymmetric total synthesis of kravanhin B has been accomplished with a linear reaction sequence of 13 steps starting from (R)‐(?)‐carvone. The synthesis features an intramolecular aldol cyclization to construct the desired cis‐fused decalin skeleton and an acid‐catalyzed dehydration and olefin isomerization to install the γ‐butenolide ring. 相似文献
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Gaoyuan Wei 《先进技术聚合物》1997,8(4):265-269
The shapes and sizes of linear and circular multiple-ring macromolecules in the framework of the Gaussian model have been numerically investigated in terms of shape factors, asphericity and prolateness factors and parameters, and shrinking factors. Simple analytic expressions for the eigenpolynomials of the Kirchhoff or architecture matrices for both linear and circular multi-rings in the limit of an infinitely large individual ring have been obtained via a new recursion method. It is found that for both types of multiple rings, shape asymmetry increases while size decreases as the number of rings increases, and that asphericity and prolateness parameters for a circular 99-ring macromolecule or a doubly stranded closed random walk have stronger dependence on dimensionality of the space in which the molecule is embedded than those of its linear counterpart. © 1997 John Wiley & Sons, Ltd. 相似文献
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第一届世界华人青年化学家学术会议暨第三届全国青年化学家学术会议在京召开魏高原,赵新生(北京大学化学与分子工程学院北京100871)TheFirstConferenceforWorldwideYoungChineseChemistsandtheThir... 相似文献
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Stereoselective Synthesis of 2‐Deoxyglycosides from Glycals by Visible‐Light‐Induced Photoacid Catalysis 下载免费PDF全文
Dr. Gaoyuan Zhao Prof. Ting Wang 《Angewandte Chemie (International ed. in English)》2018,57(21):6120-6124
The direct, photoacid‐catalyzed synthesis of 2‐deoxyglycosides from glycals is reported. A series of phenol‐conjugated acridinium‐based organic photoacids were rationally designed, synthesized, and studied alongside the commercially available phenolic catalyst eosin Y. In the presence of such a photoacid catalyst and light, synthetic glycals were activated and coupled with a range of alcohols to afford 2‐deoxyglycosides in good yields and with excellent α‐selectivity. 相似文献
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A method of obtaining the scattering spectrum that bypasses the need to solve for the configurational distribution function of the macromolecules is presented. It involves the direct calculation of averages that appear in the structure factor expression. Application of the method to Rouse coils recovers Pecora's classical results. The method is applied to obtain the coherent spectrum of a solution of “encapsulated” dumbbells for which the configurational distribution is not available. 相似文献