913196-43-7Relevant articles and documents
Iridium-catalyzed asymmetric hydrogenation of β-keto esters with new phenethylamine-derived tridentate P,N,N-ligands
Wei, De-Quan,Chen, Xiu-Shuai,Hou, Chuan-Jin,Hu, Xiang-Ping
, p. 237 - 243 (2019/01/21)
A new class of phenethylamine-derived tridentate P,N,N-ligands has been successfully developed. These ligands exhibited good performance in the Ir-catalyzed asymmetric hydrogenation of β-keto esters, affording the corresponding β-hydroxy esters in moderat
COPPER CATALYZED HALOGENATON AND REACTION PRODUCTS
-
Paragraph 0149, (2015/01/06)
A Cu(I)-catalyzed 1,3-halogen migration reaction effectively recycles an activating group by transferring a halogen from an sp2 to a benzylic carbon with good enantioselectivity and concomitant borylation of the Ar-halo bond. The resulting enantio-enriched benzyl halide can be reacted in the same vessel under a variety of conditions to form an additional carbon-heteroatom or carbon-carbon bond while maintaining high ee. The reaction can be used to efficiently prepare novel compounds and intermediates for the preparation of therapeutics and ligands for catalysis.
Modulation of multifunctional N,O,P ligands for enantioselective copper-catalyzed conjugate addition of diethylzinc and trapping of the zinc enolate
Ye, Fei,Zheng, Zhan-Jiang,Deng, Wen-Hui,Zheng, Long-Sheng,Deng, Yuan,Xia, Chun-Gu,Xu, Li-Wen
, p. 2242 - 2253 (2013/09/23)
In this work, we have successfully synthesized a new family of chiral Schiff base-phosphine ligands derived from chiral binaphthol (BINOL) and chiral primary amine. The controllable synthesis of a novel hexadentate and tetradentate N,O,P ligand that contains both axial and sp3-central chirality from axial BINOL and sp3-central primary amine led to the establishment of an efficient multifunctional N,O,P ligand for copper-catalyzed conjugate addition of an organozinc reagent. In the asymmetric conjugate reaction of organozinc reagents to enones, the polymer-like bimetallic multinuclear Cu-Zn complex constructed in situ was found to be substrate-selective and a highly excellent catalyst for diethylzinc reagents in terms of enantioselectivity (up to >99 % ee). More importantly, the chirality matching between different chiral sources, C2-axial binaphthol and sp3-central chiral phosphine, was crucial to the enantioselective induction in this reaction. The experimental results indicated that our chiral ligand (R,S,S)-L1- and (R,S)-L4-based bimetallic complex catalyst system exhibited the highest catalytic performance to date in terms of enantioselectivity and conversion even in the presence of 0.005 mol % of catalyst (S/C=20 000, turnover number (TON)=17 600). We also studied the tandem silylation or acylation of enantiomerically enriched zinc enolates that formed in situ from copper-L4-complex-catalyzed conjugate addition, which resulted in the high-yield synthesis of chiral silyl enol ethers and enoacetates, respectively. Furthermore, the specialized structure of the present multifunctional N,O,P ligand L1 or L4, and the corresponding mechanistic study of the copper catalyst system were investigated by 31P NMR spectroscopy, circular dichroism (CD), and UV/Vis absorption. Match maker: The chiral bimetallic multinuclear Cu-Zn complex that contains a novel phosphine ligand and bears matching axial and sp3-central chirality from binaphthol and chiral amine was found to be a highly efficient catalyst in the enantioselective conjugate addition of an organic zinc reagent. Copyright
Readily available chiral phosphine-aminophosphine ligands derived from 1-phenylethylamine for Rh-catalyzed enantioselective hydrogenations
Zhou, Xiao-Mao,Huang, Jia-Di,Luo, Li-Bin,Zhang, Cheng-Lu,Zheng, Zhuo,Hu, Xiang-Ping
scheme or table, p. 420 - 424 (2010/07/02)
A series of new chiral phosphine-aminophosphine ligands have been prepared via a two- or three-step transformation from commercially available and inexpensive (S)-1-phenylethylamine, and successfully used in the rhodium-catalyzed asymmetric hydrogenation
Readily available phosphine-phosphoramidite ligands for highly efficient Rh-catalyzed enantioselective hydrogenations
Huang, Jia-Di,Hu, Xiang-Ping,Duan, Zheng-Chao,Zeng, Qing-Hen,Yu, Sai-Bo,Deng, Jun,Wang, Dao-Yong,Zheng, Zhuo
, p. 4367 - 4370 (2007/10/03)
(Chemical Equation Presented) A new family of air- and moisture-stable phosphine-phosphoramidite ligands (PEAPhos) has been prepared from commercially available and inexpensive (S)-α-phenylethylamine through a two- or three-step transformation and success
