Allyl‐Transition Metal Systems

Abstract

As a confinuation of a report published in 1963, recent results in the field of allyl-transition metal complexes are described[*]. Syntheses and reactions of these compounds, as well as the bonding between metal and allyl group, are discussed. Allyl-transition metal complexes form the basis of extremely selective catalysts for homogeneous reactions of 1,3-diolefins and of olefns; the metal atoms in these "matrix" catalysts are either "bare" [**I or are bound to only a few ligands.

Chloroaluminate Ionic Liquids: from their Structural Properties to their Applications in Process Intensification

“…From an industrial point of view, despite its beneficial effect on reaction velocity, the use of a solvent is not made in order to avoid any extra separation and recycling. Following his participation to a joined meeting on Molten Salts between the French and Belgian Chemical Societies in 1989, Y. Chauvin already anticipated that, considering the cationic nature of the Dimersol ® nickel catalyst [9] (Fig. 2), ionic liquids based on chloroaluminate anions could be good solvents for the nickel catalyst stabilization and immobilization.…”

Oligomerization of Monoolefins by Homogeneous Catalysts

“…That is why, at high conversion of propene (>80%), the selectivity to dimers depends on the type of reactor used. Cationic nickel complexes are generally non selective, but addition of phosphines can have a considerable effect on the regioselectivity of propene dimerization as shown by Wilke et al [18] with well defined cationic η 3 -allylnickel complexes (Fig. 1).…”

Alkali Metal Complexes of Silyl‐Substituted ansa‐(Tris)allyl Ligands: Metal‐, Co‐Ligand‐ and Substituent‐Dependent Stereochemistry

“…[2] In a coordination chemistry setting, despite their widespread use in catalysis, allyl complexes of transition metals are notorious for their thermal instability and air-sensitivity. [3] In contrast, silyl-substituted allyl ligands have allowed access to a broad range of kinetically stabilized, isolable allyl complexes of d-, [4][5][6][7][8][9][10][11][12] f- [13][14][15][16][17][18][19][20] and p-block, [21,22] metals. Whereas structural characterization of metal allyl compounds featuring allyl ligands with low steric demands has been rare, in many cases it has been possible to structurally characterize silylsubstituted metal allyl complexes by X-ray crystallography.…”