183596-33-0Relevant articles and documents
Silver-Mediated [3 + 2] Cycloaddition of Azomethine Ylides with Trifluoroacetimidoyl Chlorides for the Synthesis of 5-(Trifluoromethyl)imidazoles
Yang, Hefei,Lu, Shu-Ning,Chen, Zhengkai,Wu, Xiao-Feng
supporting information, p. 4361 - 4370 (2021/03/09)
A silver-mediated [3 + 2] cycloaddition of azomethine ylides with trifluoroacetimidoyl chlorides for the rapid assembly of 5-(trifluoromethyl)imidazoles has been developed. Notable features of the reaction include readily accessible reagents, a broad substrate scope, and high efficiency. The protocol can be successfully applied to construct the analogue of the specific allosteric modulator of GABAA receptors. The silver species could be recycled by a simple operation.
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.
Ag2CO3/CA-AA-amidphos multifunctional catalysis in the enantioselective 1,3-dipolar cycloaddition of azomethine ylides
Wang, Haifei,Deng, Qifu,Zhou, Zhipeng,Hu, Shunqin,Liu, Zhiguo,Zhou, Li-Yi
supporting information, p. 404 - 407 (2016/02/18)
The new Ag2CO3/CA-AA-amidphos complexes have been demonstrated as highly efficient multifunctional catalysts in the asymmetric 1,3-dipolar cycloaddition of azomethine ylides. Under optimal conditions, highly functionalized endo-4 pyrrolidines were obtained with excellent yields (up to 99% yield) and enantioselectivities (up to 96% ee).
