212317-62-9Relevant academic research and scientific papers
Preparation and reactions of palladium(0)-olefin complexes with iminophosphine ligands
Antonaroli, Simonetta,Crociani, Bruno
, p. 137 - 146 (2007/10/03)
The complexes [Pd(η2-ol){o-(Ph2P)-C6H4-CH=NR}] [ol, dimethyl fumarate (dmf), 1,4-naphtoquinone (nq), fumaronitrile (fn); R=C6H4OMe-4, CMe3, Me, bornyl] can be prepared in good yields from the reaction of the allyl derivatives [Pd(η3-C3H5) {o-(Ph2P)-C6H4-CH=NR}]BF4 with an excess of NHEt2 in the presence of the activated olefin ol. The complex [Pd(η2-ma){o-(Ph2P)-C6H4-CH=NC6H4OMe-4}] (ma, maleic anhydride) is more conveniently obtained via olefin substitution from [Pd(η2-dmf){o-(Ph2P)-C6H4-CH=NC6H4OMe-4}]. The α-diimine ligand of [Pd(η2-fn)(py-2-CH=NC6H4OMe-4)] is quantitatively displaced by the appropriate iminophosphine to give [Pd(η2-fn){o-(Ph2P)-C6H4-CH=NC6H4OMe-4}]. The new zerovalent complexes with P-N ligands are characterized by multinuclear NMR spectroscopy. In solution, olefin rotation or olefin exchange are generally slow. The compound [Pd(η2-fn){o-(Ph2P)-C6H4-CH=NC6H4OMe-4}] reacts with a second molecule of iminophosphine yielding [Pd(η2-fn){o-(Ph2P)-C6H4-CH=NC6H4OMe-4}2] in which the iminophosphines act essentially as P-monodentate ligands. [Pd(η2-dmf) {o-(Ph2P)-C6H4-CH=NC6H4OM e-4}] undergoes fast oxidative addition of allyl chloride to [Pd(η3-C3H5){o-(Ph2P)-C6H4-CH=NC6H4OMe-4}]+.
