Gas-Phase Study of Phenylacetylene and Norbornadiene on a Palladium(II) Phosphinous Acid Complex: Importance of the Order of Introduction of the Organic Partners.

Pd(II) acetate complexes with phosphinous acids such as tert-butyl(phenyl)phosphinous acid (PAPd) were successfully applied in a new [2 + 1] cycloaddn. reaction between norbornadiene (NBD) and phenylacetylene (PhCCH) to produce exo-phenylmethylidenecyclopropane in the soln. phase. In the present study, collision-activated reaction (CAR)/collision-induced dissocn. (CID) mass spectral expts. were performed on a cationic Pd(II) complex (Pd(OPPhtBu)2H ion, [a]+). These expts. were useful for the identification of the reactive intermediates in the gas phase. From the results of the collision-activated reactions on this particular Pd(II) complex ion with phenylacetylene and norbornadiene, the authors demonstrated the essential role of the order of addn. of org. partners on the efficiency to form the diadduct ion [a + PhCCH + NBD]+. Theor. calcns. combined with mass spectrometry expts. support 1st a change in coordination mode of alkyne ($η$2 into $η$1) prior to the coordination of NBD, yielding an insertion product. However, in this gas-phase reaction procedure, the role of the acetate ligand in the reactivity of the neutral complex is not addressed. [on SciFinder(R)]

Références

Titre
Gas-Phase Study of Phenylacetylene and Norbornadiene on a Palladium(II) Phosphinous Acid Complex: Importance of the Order of Introduction of the Organic Partners.
Type de publication
Article de revue
Année de publication
2009
Revue
Organometallics
Volume
28
Pagination
2735–2743
ISSN
0276-7333
Soumis le 12 avril 2018