Chiral Phosphine Ligands Derived from Sugars. 3. Syntheses, Structures, and Spectroscopic Properties of Gold(I) Complexes with Chiral Phosphines from Glucose. X-ray Structures of [Au(2-MBPA)Cl] and [Au(3-MBPA)(2-pyS)]

1996 ◽  
Vol 35 (10) ◽  
pp. 2742-2746 ◽  
Author(s):  
Ji-Cheng Shi ◽  
Xiao-Ying Huang ◽  
Da-Xu Wu ◽  
Qiu-Tian Liu ◽  
Bei-Sheng Kang
Keyword(s):  
Spectroscopic Properties ◽  
Phosphine Ligands ◽  
X Ray ◽  
Chiral Phosphine Ligands ◽  
Chiral Phosphines

scholarly journals Copper-catalyzed asymmetric methylation of fluoroalkylated pyruvates with dimethylzinc

2018 ◽  
Vol 14 ◽  
pp. 576-582 ◽  
Author(s):  
Kohsuke Aikawa ◽  
Kohei Yabuuchi ◽  
Kota Torii ◽  
Koichi Mikami
Keyword(s):  
Copper Catalyst ◽  
Phosphine Ligand ◽  
Phosphine Ligands ◽  
Tertiary Alcohols ◽  
Chiral Phosphine Ligands ◽  
Asymmetric Methylation ◽  
Chiral Phosphines ◽  
Catalytic Asymmetric ◽  
High Yields

The catalytic asymmetric methylation of fluoroalkylated pyruvates is shown with dimethylzinc as a methylating reagent in the presence of a copper catalyst bearing a chiral phosphine ligand. This is the first catalytic asymmetric methylation to synthesize various α-fluoroalkylated tertiary alcohols with CF3, CF2H, CF2Br, and n-C n F2 n +1 (n = 2, 3, 8) groups in good-to-high yields and enantioselectivities. Axial backbones and substituents on phosphorus atoms of chiral phosphine ligands critically influence the enantioselectivity. Moreover, the methylation of simple perfluoroalkylated ketones is found to be facilitated by only chiral phosphines without copper.

Rhodium-Catalyzed, Phosphorus(III)-Directed Hydroarylation of Internal Alkynes: Facile and Efficient Access to New Phosphine Ligands

Synlett ◽  
2020 ◽  
Author(s):  
Minyan Wang ◽  
Zhuangzhi Shi ◽  
Huanhuan Luo ◽  
Dawei Wang
Keyword(s):  
High Selectivity ◽  
Enantiomeric Excess ◽  
Phosphine Ligands ◽  
Rapid Construction ◽  
Efficient Access ◽  
Internal Alkynes ◽  
Great Progress ◽  
Chiral Phosphine Ligands ◽  
Optimized Conditions ◽  
Made In

AbstractOrganophosphines are an important class of ligands widely used in organic chemistry. Although great progress has recently been made in the rapid construction of new phosphines through Rh- or Ru-catalyzed C–H bond functionalizations, synthetic access to more diverse phosphines remains a challenge. We describe an efficient process for the rhodium-catalyzed phosphorus(III)-directed hydroarylation of internal alkynes to generate various alkenylated and 2′,6′-dialkenylated biarylphosphines with high selectivity. A range of diverse alkynes and phosphines were effectively prepared with broad functional-group compatibility under the optimized conditions. In addition, the developed protocol can be extended to modify chiral phosphine ligands, providing enantioenriched alkenylated phosphines without erosion of the enantiomeric excess.

Systhesis, Characterization and Spectroscopic Properties of (2E,6E)-2,6-Bis(2,3,4-tri-methoxy-benzylidene)cyclohexanone

2011 ◽  
Vol 396-398 ◽  
pp. 2338-2341
Author(s):  
Xing Chuan Wei ◽  
Zhi Li Liu ◽  
Kun Zhang ◽  
Zhi Yun Du ◽  
Xi Zheng
Keyword(s):  
Crystal Structure ◽  
Acetic Acid ◽  
Hydrogen Bonds ◽  
Title Compound ◽  
Spectroscopic Properties ◽  
Spectral Studies ◽  
Double Bonds ◽  
X Ray ◽  
Π Interactions ◽  
X Ray Crystallography

In this paper, (2E,6E)-2,6-Bis(2,3,4-tri-methoxy -benzylidene)cyclohexanone (omitted as tmbcho) (1) was obtained by the reaction of acetic acid, tetrahydrofuran, cyclohexanone and 2,3,4-tri-methoxy-benzaldehyde. Three non-classic hydrogen bonds were observed in the compound. X-ray crystallography shows that the crystal structure is stabilized by intermolecular C-H•••π interactions and it contains plenty of conjugated double bonds. The title compound was characterized by UV-vis and fluorescent spectral studies.

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