151073-48-2Relevant articles and documents
Highly enantioselective hydrogenation of α-dehydroamino esters and itaconates with triphosphorous bidentate ligands and the unprecedented solvent effect thereof
Zhang, Weicheng,Zhang, Xumu
, p. 1020 - 1023 (2007)
(Chemical Equation Presented) An X-ray diffraction experiment revealed an interesting triphosphorous bidentate coordination in a Pd(II) complex of a phosphine-phosphoramidite ligand 1, which showed excellent enantioselectivity (up to 99.4% ee) in Rh-catalyzed hydrogenation of α-dehydroamino esters in acetone. A dramatic solvent effect was found in the hydrogenation of itaconates, which induces opposite chiralities of the product with the same catalytic system by the use of different solvents (e.g., 99.6% ee (R) in TFE vs 71.2% ee (S) in methyl ethyl ketone).
Synthesis of novel BINOL-derived chiral bisphosphorus ligands and their application in catalytic asymmetric hydrogenation
Zhou, Yong-Gui,Zhang, Xumu
, p. 1124 - 1125 (2002)
Some novel ortho-substituted BINOL-derived bisphosphorus ligands (o-BINAPO and o-NAPHOS) were synthesis from readily available (S)-BINOL; these ligands showed excellent enantioselectivities (up to 99% ee) in Rh(I)-catalyzed asymmetric hydrogenation of fun
Topology-Based Functionalization of Robust Chiral Zr-Based Metal-Organic Frameworks for Catalytic Enantioselective Hydrogenation
Jiang, Hong,Zhang, Wenqiang,Kang, Xing,Cao, Ziping,Chen, Xu,Liu, Yan,Cui, Yong
, p. 9642 - 9652 (2020/07/02)
The design and development of robust and porous supported catalysts with high activity and selectivity is extremely significant but very challenging for eco-friendly synthesis of fine chemicals and pharmaceuticals. We report here the design and synthesis of highly stable chiral Zr(IV)-based MOFs with different topologies to support Ir complexes and demonstrate their network structures-dependent asymmetric catalytic performance. Guided by the modulated synthesis and isoreticular expansion strategy, five chiral Zr-MOFs with a flu or ith topology are constructed from enantiopure 1,1′-biphenol-derived tetracarboxylate linkers and Zr6, Zr9, or Zr12 clusters. The obtained MOFs all show high chemical stability in boiling water, strongly acidic, and weakly basic aqueous solutions. The two flu MOFs featuring the dihydroxyl groups of biphenol in open and large cages, after sequential postsynthetic modification with P(NMe2)3 and [Ir(COD)Cl]2, can be highly efficient and recyclable heterogeneous catalysts for hydrogenation of α-dehydroamino acid esters with up to 98% ee, whereas the three ith MOFs featuring the dihydroxyl groups in small cages cannot be installed with P(NMe2)3 to support the Ir complex. Incorporation of Ir-phosphorus catalysts into Zr-MOFs leads to great enhancement of their chemical stability, durability, and even stereoselectivity. This work therefore not only advances Zr-MOFs as stable supports for labile metal catalysts for heterogeneous asymmetric catalysis but also provides a new insight into how highly active chiral centers can result due to the framework topology.
A supramolecularly tunable chiral diphosphine ligand: Application to Rh and Ir-catalyzed enantioselective hydrogenation
Zhang, Xi-Chang,Hu, Yi-Hu,Chen, Chuan-Fu,Fang, Qiang,Yang, Li-Yao,Lu, Ying-Bo,Xie, Lin-Jie,Wu, Jing,Li, Shijun,Fang, Wenjun
, p. 4294 - 4299 (2016/07/06)
A supramolecularly tunable chiral bisphosphine ligand bearing two pyridyl-containing crown ethers, (-) or (+)-Xyl-P16C6-Phos, was fabricated and utilized in the Rh-catalyzed asymmetric hydrogenation of α-dehydroamino acid esters and Ir-catalyzed asymmetric hydrogenation of quinolines in high yields with excellent enantioselectivities (90-99% ee). Up to a 22% enhancement in enantioselectivity was achieved by the addition of certain amounts of alkali ions (Li+, Na+ or K+), which could be selectively recognized and effectively complexed by the crown ethers on the chiral Xyl-P16C6-Phos.
