Fréchet‐Type Pallado‐Dendrimers Containing Bis(pyrazolyl)methane Ligands

Abstract

AbstractNeutral and cationic {bis(3,5‐dimethylpyrazol‐1‐yl)methane}palladium(II) complexes of general formula [PdClX{RCH(3,5‐Me2pz)2}] (X = Cl or Me) or [PdMe(MeCN){RCH(3,5‐Me2pz)2}][BArf4], where R is a benzyl or benzyloxycarbonyl group or a poly(aryl ether) Fréchet‐type dendron, have been synthesized and fully characterized, including by X‐ray diffraction methods in some cases. These palladium complexes have been evaluated as catalyst precursors in the Heck reaction between para‐iodotoluene and methyl acrylate. The active catalytic species formed from these precursors are apparently not coordinated to the bis(pyrazolyl)methane ligands.