The use of diphosphine ligands in catalysis has allowed the optimization of industrial processes and has led to the development of new catalytic systems.
12.
Diphosphine ligands such as dppe, which has a bite angle of about 90? span the equatorial and apical positions ( AE isomer ).
13.
As an independent scientist at the University of Toronto, he developed a rational approach to chiral diphosphine ligands, the premier member being chiraphos.
14.
For the above example, the unwanted ?-hydride elimination is prevented by using a diphosphine where the two phosphorus atoms are fixed apart in space.
15.
Although the parameter can be applied generally to any chelating ligand, it is commonly applied to describe diphosphine ligands, which can adopt a wide range of chelate ring sizes.
16.
Furthermore, studies using Xantphos ligands ( ligands with bulky backbones ) in hydroformylation have indicated an increase in the rate of catalysis in metal complexes that contain diphosphine ligands with larger bite angles.
17.
Developed by Noyori, BINAP ( 2, 2'- diphenylphosphino-1, 1'- binaphthyl ) is a family of chiral diphosphine ligands featuring two triarylphosphine moieties installed on a binaphthalene backbone.
18.
In an effort to create rhodium complexes in which the phosphine ligands preferentially occupy the equatorial positions, the use of diphosphine ligands with wide bite angles such as BISBI ( Figure 5 ) has been investigated.
19.
Conversion of ethylene to diethyl ketone using a cobalt carbonyl, while the reaction used a cobalt carbonyl diphosphine complex for clarity the reaction has been drawn out, assuming that a cobalt carbonyl is responsible for the reaction
20.
An early demonstration of this approach was the Rh-catalyzed hydrogenation of enamides as precursors to the drug L-DOPA . To achieve asymmetric reduction, these catalyst are made chiral by use of chiral diphosphine ligands.
