139575-14-7Relevant articles and documents
Copper/GanPhos-Catalyzed 1,3-Dipolar Cycloaddition of Azo?-methine Ylides: An Efficient Access to Chiral Pyrrolidine Spirocycles
Gan, Zhenjie,Li, Ke,Zhang, Hui,Li, Er-Qing
supporting information, p. 1331 - 1340 (2020/11/30)
A highly efficient copper/GanPhos-catalyzed 1,3-dipolar cyclo?-addition?-of azomethine ylides is reported. This viable transformation provides a series of optically active spiro[dihydronaphthalene-2,3′-pyrrolidine]s, bearing one spiro quaternary and three tertiary stereogenic centers, in good yields and with high ee values. This protocol features high diastereo- A nd enantioselectivity, broad substrate scope and mild reaction conditions.
Copper(i)/Ganphos catalysis: enantioselective synthesis of diverse spirooxindoles using iminoesters and alkyl substituted methyleneindolinones
Cui, Hao,Duan, Zheng,Li, Er-Qing,Li, Ke,Mathey, Fran?ois,Song, Manman,Wang, Congcong,Wang, Yue,Wei, Donghui
supporting information, p. 3740 - 3746 (2020/06/03)
A copper-catalyzed asymmetric 1,3-dipolar cycloaddition of glycine iminoesters with alkyl substituted 3-methylene-2-oxindoles is described. By usingde novodesign of P-stereogenic phosphines as ligands, spiro[pyrrolidin-3,3'-oxindole]s are generated in good to excellent yields with high asymmetric induction. A further reduced catalyst loading of 0.1 mol% is sufficient to achieve a satisfactory enantioselectivity of 90% ee. The DFT calculations suggest the second Michael addition of the 1,3-dipole to be the rate- andenantio-determining step. A key feature of this 1,3-dipolar cycloaddition is the wide substrate applicability, even with alkyl aldehyde-derived azomethine ylide; thus it has streamlined a highly enantioselective access to a new class of antiproliferative agents, MDM2-p53.
Well-Designed Phosphine-Urea Ligand for Highly Diastereo- and Enantioselective 1,3-Dipolar Cycloaddition of Methacrylonitrile: A Combined Experimental and Theoretical Study
Xiong, Yang,Du, Zhuanzhuan,Chen, Haohua,Yang, Zhao,Tan, Qiuyuan,Zhang, Changhui,Zhu, Lei,Lan, Yu,Zhang, Min
supporting information, p. 961 - 971 (2019/01/14)
A novel chiral phosphine-urea bifunctional ligand has been developed for Cu-catalyzed asymmetric 1,3-dipolar cycloaddition of iminoesters with methacrylonitrile, a long-standing challenging substrate in asymmetric catalysis. Distortion-interaction energy analysis based on density functional theory (DFT) calculations reveals that the distortion energy plays an important role in the observed enantioselectivity, which can be attributed to the steric effect between the phosphine ligand and the dipole reactant. DFT calculations also indicate that nucleophilic addition is the enantioselectivity-determining step and hydrogen bonding between the urea moiety and methacrylonitrile assists in control of the diastereo- and enantioselectivity. By a combination of metal catalysis and organocatalysis, excellent diastereo- and enantioselectivities (up to 99:1 diastereomeric ratio, 99% enantiomeric excess) as well as good yields are achieved. A wide range of substitution patterns of both iminoester and acrylonitrile is tolerated by this catalyst system, providing access to a series of highly substituted chiral cyanopyrrolidines with up to two quaternary stereogenic centers. The synthetic utility is demonstrated by enantioselective synthesis of antitumor agent ETP69 with a pivotal nitrile pharmacophore and an all-carbon quaternary stereogenic center.