761402-24-8Relevant articles and documents
Palladium-Catalyzed Asymmetric Decarboxylative [4+2] Dipolar Cycloaddition of 4-Vinyl-1,3-dioxan-2-ones with α,β-Disubstituted Nitroalkenes Enabled by a Benzylic Substituted P,N-Ligand
Chen, Di,Ding, Chang-Hua,Du, Juan,Hou, Xue-Long,Hua, Yuan-Da,Huang, Shuai,Jiang, Yang-Jie
, (2020)
The Pd-catalyzed asymmetric [4+2] cycloaddition reaction of an aliphatic 1,4-dipole with singly activated electron-deficient alkenes is realized for the first time, enabled by using a newly developed benzylic substituted P,N-ligand, affording tetrahydropyrans having three continuous chiral centers in high yields with high diastereo-and enantioselectivities. The rational transition states of the reaction as well as the role of the benzylic chiral center are proposed.
A dramatic switch of enantioselectivity in asymmetric heck reaction by benzylic substituents of ligands
Wu, Wen-Qiong,Peng, Qian,Dong, Da-Xuan,Hou, Xue-Long,Wu, Yun-Dong
experimental part, p. 9717 - 9725 (2009/02/04)
A series of benzylic substituted P,N-ligands 1 and 2 have been synthesized. The Pd-complexes of these ligands show high catalytic activity and enantioselectivity in catalyzing the asymmetric Heck reaction. A dramatic switch in enantioselectivity is realized using ligands with and without substituents at the benzylic position of the ligand. Ligands 1 with H as the substituents offer products in (R)-configuration while ligands 2 with the methyl as substituents result in (S)-configuration products. In most cases high enantioselectivities are achieved. Density functional theory calculations on the reaction mechanism as well as X-ray analysis of 1a-PdCl2 and 2a-PdCl2 complexes provide a rational explanation for the above observations.
Synthesis of new chiral benzylically substituted P,N-ligands and their applications in the asymmetric Heck reaction
Hou, Xue-Long,Dong, Da Xuan,Yuan, Ke
, p. 2189 - 2191 (2007/10/03)
A series of new chiral P,N-ligands with substituents at the benzylic position has been prepared. Their high catalytic activity is shown in the Pd-catalyzed asymmetric Heck reaction and allylic substitution reaction.
