An unusual product distribution from the reaction of Pd(η3-1-PhC3H4)(η5-C5H5) with a deficiency of PPh3 in the presence of bromobenzene

Dinuclear PdIcomplexes with bridging allyl and related ligands

“…This is in agreement with results from Baird and co-workers who demonstrated that (m-cinnamyl)(m-Br)Pd 2 (PPh 3 ) 2 is a poor catalyst for the Buchwald-Hartwig reaction. 57 However, at elevated temperature (40 1C) both the monomeric and dinuclear precatalysts in our study give essentially comparable activity. We propose that all precatalysts are able to relatively efficiently access the monoligated Pd 0 active species at 40 1C and thus there is a considerably smaller difference in precatalyst activity at this temperature.…”

“…In a series of related studies Baird has demonstrated that the treatment of (Cp)(allyl)Pd and analogues with two equivalents of tertiary phosphines generates complexes of the type (m-Cp)(m-allyl)Pd 2 L 2 as intermediates before the eventual formation of phosphine supported Pd 0 complexes. 54,[56][57][58] The steric bulk of the phosphine ligand controls the number of phosphines coordinated to Pd 0 . Leoni and co-workers have studied the reaction (Cp)(allyl)Pd with multiple equivalents of the secondary phosphine HPCy 2 and in this case a species with a bridging allyl ligand is also formed.…”