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Wen-Jun Yue Jun-Zhao Xiao Shuai Zhang Prof. Dr. Liang Yin 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2020,132(18):7123-7128
1,2-Bisphosphines have been identified as one class of important and powerful chiral ligands in asymmetric catalysis with transition metals. Herein, a copper(I)-catalyzed asymmetric hydrophosphination of α,β-unsaturated phosphine sulfides was developed with the assistance of “soft–soft” interaction between copper(I)-catalyst and the phosphine sulfide moiety, which afforded 1,2-bisphosphine derivatives with diversified electronic nature and steric hindrance in high to excellent yields with high to excellent enantioselectivity. Moreover, the challenging catalytic asymmetric hydrophosphination/protonation reaction was achieved with excellent enantioselectivity. Strikingly, the dynamic kinetic resolution of racemic diarylphosphines was also successfully carried out with high to excellent diastereo- and enantioselectivities. Interestingly, the nucleophilic copper(I)-diphenylphosphide species was characterized by 31P NMR spectrum and mass spectrum. At last, three products were transformed to chiral 1,2-bisphosphines, which were employed as ligands in Rh-catalyzed asymmetric hydrogenation of α-amino-α,β-unsaturated ester. The α-amino acid derivative was produced in high enantioselectivity, which demonstrated the utility of the present methodology. 相似文献
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Feng Zhong Qi‐Yan Xue Liang Yin 《Angewandte Chemie (International ed. in English)》2020,59(4):1562-1566
Chiral 2,3‐allenols were constructed through copper(I)‐catalyzed asymmetric direct alkynylogous aldol reaction. With aromatic and heteroaromatic aldehydes, the alkynylogous aldol reaction with (R)‐DTBM‐SEGPHOS as the ligand proceeded smoothly to furnish the products in excellent regioselectivity with good to high diastereoselectivity and excellent enantioselectivity. In the cases of aliphatic aldehydes, esters of but‐2‐yn‐1‐ol as the substrates and (R,R)‐Ph‐BPE as the ligand were found to be crucial to get good to high regio‐ and diastereoselectivity. The produced chiral 2,3‐allenols are easily transformed into synthetically useful 2‐furanones through cyclization. Finally, the developed method was successfully applied in the rapid synthesis of two chiral intermediates toward the synthesis of two pharmaceutically active compounds that have been proposed for the treatment of neurological disorders. 相似文献
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Laëtitia Palais Alexandre Alexakis Prof. Dr. 《Chemistry (Weinheim an der Bergstrasse, Germany)》2009,15(40):10473-10485
SimplePhos ligands represent a novel class of monodentate chiral ligands based on a chiral amine moiety and flexible diaryl groups on the phosphorous atom. They can be easily prepared by two different pathways and they can be highly functionalised. Herein we report the copper‐catalysed asymmetric conjugate addition of diethyl zinc and trialkylaluminium reagents with SimplePhos ligands, which gives high enantioselectivity with cyclic enones, acyclic enones and nitro‐olefins, with up to 98.6 % ee. Of particular interest is the reaction of trialkylaluminium reagents with a wide range of 3‐substituted enones, thus allowing the formation of stereogenic quaternary carbon centres. 相似文献
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Dr. Kodai Saito Yuki Kajiwara Prof. Dr. Takahiko Akiyama 《Angewandte Chemie (International ed. in English)》2013,52(50):13284-13288
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Quangang Chen Yu Tang Tianyu Huang Prof. Dr. Xiaohua Liu Dr. Lili Lin Prof. Dr. Xiaoming Feng 《Angewandte Chemie (International ed. in English)》2016,55(17):5286-5289
The highly enantioselective alkynylation of isatins, catalyzed by a bifunctional guanidine/CuI catalyst under mild reaction conditions, is described. The reaction is broad in scope with respect to alkyl/aryl‐substituted terminal alkynes and substituted isatins, thus affording bioactive propargylic alcohols in excellent yields and enantioselectivities. 相似文献
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Efficient Synthesis of Chiral Trisubstituted 1,2‐Allenyl Ketones by Catalytic Asymmetric Conjugate Addition of Malonic Esters to Enynes 下载免费PDF全文
Qian Yao Yuting Liao Dr. Lili Lin Xiaobin Lin Jie Ji Prof. Dr. Xiaohua Liu Prof. Dr. Xiaoming Feng 《Angewandte Chemie (International ed. in English)》2016,55(5):1859-1863
An N,N′‐dioxide/scandium(III) complex catalyzed, highly efficient conjugate addition of malonic esters to enynes is described. A range of trisubstituted 1,2‐allenyl ketones were obtained in high yields (up to 99 %) with good d.r. (up to 95/5) and excellent ee values (97 %–99 %). Moreover, the products could be easily transformed into chiral furan and 5‐hydroxypyrazoline derivatives, both of which are important skeletons of many biologically active compounds and pharmacologicals. 相似文献
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Dr. Andreas Ole Termath B. Sc. Hanna Sebode M. Sc. Waldemar Schlundt Dr. René T. Stemmler Dr. Thomas Netscher Priv.‐Doz. Dr. Werner Bonrath Prof. Dr. Hans‐Günther Schmalz 《Chemistry (Weinheim an der Bergstrasse, Germany)》2014,20(38):12051-12055
By introducing a disposable activating substituent at C‐3, the asymmetric 1,4‐addition to a notoriously unreactive 2‐substituted chromenone was achieved with high levels of (2R)‐stereoselectivity in the presence of a chiral CuI‐phosphoramidite complex as a catalyst. This paved the way for an efficient and conceptually novel synthesis of (R,R,R)‐α‐tocopherol from readily available starting materials. 相似文献
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Matthew V. Joannou Brandon S. Moyer Matthew J. Goldfogel Prof. Simon J. Meek 《Angewandte Chemie (International ed. in English)》2015,54(47):14141-14145
A catalytic protocol for the diastereoselective synthesis of anti‐1,2‐hydroxyboronates is described. The process provides access to secondary alkyl organoborons. The deborylative 1,2‐addition reactions of alkyl 1,1‐diborons proceed in the presence of a silver(I) salt with either KOtBu or nBuLi as an activator. The catalytic diastereoselective protocol can be extended to aryl, alkenyl, and alkyl aldehydes with up to 99:1 d.r. 相似文献
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IntroductionAsymmetriccatalyticcyclopropanationofolefinswithdiazocompoundsisoneofthemostusefulmethodsforthesynthesisofchiralcyclopropanes .1Anumberofefficientchiralligands ,particularlybisnitrogenligands ,havebeendeveloped ,andexcellentenantioselectiviti… 相似文献
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