335605-65-7Relevant academic research and scientific papers
A new class of anionic phosphinooxazoline ligands in palladium and ruthenium complexes: Catalytic properties for the transfer hydrogenation of acetophenone
Braunstein,Naud,Rettig
, p. 32 - 39 (2007/10/03)
The synthesis of the cationic Pd complex [Pd(dmba)(PCH2-oxazoline)]Cl [PCH2-oxazoline = 2-oxazoline-2-ylmethyl)diphenylphosphine] (2) has allowed for the first time the observation of hemilabile behaviour for a phosphinooxazoline ligand. This molecular dynamics is stopped upon removal of the chloride anion, by reaction with either NH4PF6, which retains the cationic nature of the complex, or ButOK. The latter reaction leads to the formation of the first example of a Pd complex bearing an anionic phosphinooxazoline ligand, [Pd(dmba){Ph2PCH - -...C( - -...N)CH2CH2O}], abreviated [Pd(dmba)(PCH-oxazoline)] (7), the anionic charge resulting from the monodeprotonation of the PCH2 group. Following this methodology, the Ru complex [RuCl(p-cymene){Ph2PCH - -...C( - -...N)CH2CH2O}], abreviated [RuCl(η6-p-cymene)(PCH-oxazoline)] (8) and containing this four-electron chelating anionic ligand, was prepared and shown to be more reactive for the catalytic transfer hydrogenation of acetophenone in propan-2-ol than the analogous complex bearing the neutral phosphinooxazoline ligand PCH2-oxazoline. The crystal structure of cis-[Pd{Ph2PCH - -...C( - -...N)CH2CH2O}2], abbreviated cis-[Pd(PCH-oxazoline)2] (6), was determined by X-ray diffraction.
