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Prof. Dr. Barry M. Trost Dr. Zhijun Zuo 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2020,132(3):1259-1263
A novel Pd0-catalyzed asymmetric [4+3] annulation reaction of two readily accessible starting materials has been developed for building seven-membered heterocyclic architectures. The potential [3+2] side pathway could be suppressed though fine tuning of the conditions. A broad scope of cycloaddition donors and acceptors participated in the transformation with excellent chemo-, regio-, diastereo-, and enantioselectivtities, leading to valuable tetrahydroazepines and benzo[b]oxepines. 相似文献
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Chuanqi Hou Dr. Pinhong Chen Prof. Dr. Guosheng Liu 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2020,132(7):2757-2761
The first asymmetric PdII-catalyzed aminofluorination of unactivated alkenes using chiral quinoline-oxazolines (Quox) as ligands has been developed. This reaction provides easy access to a wide array of enantiomerically enriched β-fluoropiperidines in good yields and with excellent enantioselectivity. Notably, Et4NF⋅3 HF as a readily accessible nucleophilic fluoride source was found to play an essential role in the enantioselective control, and CsOCF3 also acts a key additive to improve the excellent ee value of products. 相似文献
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Guozhu Li Qinzhe Liu Laxmaiah Vasamsetty Weicong Guo Prof. Dr. Jun Wang 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2020,132(9):3503-3507
A ruthenium(II)-catalyzed asymmetric intramolecular hydroarylation assisted by a chiral transient directing group has been developed. A series of 2,3-dihydrobenzofurans bearing chiral all-carbon quaternary stereocenters have been prepared in remarkably high yields (up to 98 %) and enantioselectivities (up to >99 % ee). By this methodology, a novel asymmetric total synthesis of CB2 receptor agonist MDA7 has been successfully developed. 相似文献
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Linli Zhang Yitian Tang Zhaobin Han Kuiling Ding 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2019,131(15):5027-5031
A series of MnI complexes containing lutidine‐based chiral pincer ligands with modular and tunable structures has been developed. The complex shows unprecedentedly high activities (up to 9800 TON; TON=turnover number), broad substrate scope (81 examples), good functional‐group tolerance, and excellent enantioselectivities (85–98 % ee) in the hydrogenation of various ketones. These aspects are rare in earth‐abundant metal catalyzed hydrogenations. The utility of the protocol have been demonstrated in the asymmetric synthesis of a variety of key intermediates for chiral drugs. Preliminary mechanistic investigations indicate that an outer‐sphere mode of substrate–catalyst interactions probably dominates the catalysis. 相似文献
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Ya Chen Yixiao Pan Yan‐Mei He Qing‐Hua Fan 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2019,131(47):16987-16990
A highly enantioselective iridium‐ or ruthenium‐catalyzed intermolecular reductive amination/asymmetric hydrogenation relay with 2‐quinoline aldehydes and aromatic amines has been developed. A broad range of sterically tunable chiral N,N′‐diaryl vicinal diamines were obtained in high yields (up to 95 %) with excellent enantioselectivity (up to >99 % ee). The resulting chiral diamines could be readily transformed into sterically hindered chiral N‐heterocyclic carbene (NHC) precursors, which are otherwise difficult to access. The usefulness of this synthetic approach was further demonstrated by the successful application of one of the chiral vicinal diamines and chiral NHC ligands in a transition‐metal‐catalyzed asymmetric Suzuki–Miyaura cross‐coupling reaction and asymmetric ring‐opening cross‐metathesis, respectively. 相似文献
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