Flapper, Jitte published the artcileNickel and Palladium Complexes of New Pyridine-Phosphine Ligands and Their Use in Ethene Oligomerization, Application of Dimesitylphosphine oxide, the publication is Organometallics (2009), 28(11), 3272-3281, database is CAplus.
New pyridine-phosphine ligands of general structure 2-[2-(diarylphosphino)ethyl]pyridine were developed. The phosphorus substituents in these bidentates are 2-tolyl, 2-anisyl, and mesityl. The ligands could be conveniently synthesized in good yields. The nickel dichloride complexes of the ligands are paramagnetic. The metal centers have a distorted tetrahedral geometry, as was evident from the crystal structures and the magnetic moments in solution The neutral methylpalladium chloride and the cationic methylpalladium complexes have a distorted square-planar geometry around the metal center. For the complexes of two of the ligands, an anagostic C-H¡¤¡¤¡¤Pd interaction of a ligand-proton with the palladium atom was observed in the crystal structures and in solution These interactions probably were related to hindered inversion of the six-membered metallocycle, which was observed in VT-NMR measurements. The complexes of the mesityl-substituted ligand show neither hindered inversion of the metal chelate ring nor a sign of Pd¡¤¡¤¡¤H interactions. The nickel complexes form active catalysts for the oligomerization of ethene after MAO activation. The bulky 2-tolyl and mesityl groups suppress isomerization of the growing chain, reflected in a high 1-butene selectivity. For the complex made from the ligand with the most bulky (mesityl) substituents, this selectivity was 90%. The anisyl substituents induced a different catalytic behavior of the corresponding nickel complex. Selectivity for 1-butene was lower, but the productivity was higher, with a turnover frequency of 65 ¡Á 103 (mol C2H4)/(mol/Ni/h)-1. The cationic palladium complexes showed a very low activity in ethene oligomerization. Butenes were the major product, but significant amounts of higher olefins were formed as well.
Organometallics published new progress about 23897-16-7. 23897-16-7 belongs to catalysis-chemistry, auxiliary class Aryl phosphine ligand,Mono-phosphine Ligands, name is Dimesitylphosphine oxide, and the molecular formula is C18H23OP, Application of Dimesitylphosphine oxide.
Referemce:
https://courses.lumenlearning.com/boundless-chemistry/chapter/catalysis/,
Catalysis – Wikipedia