Synthesis and reactivity of a nucleophilic palladium(II) carbene

Abstract

Two formal palladium carbene complexes, [PC(sp2)P]Pd(PR3) (3: R = Me; 4: R = Ph) were isolated and characterized from [PC(sp3)H2P] ([PC(sp3)H2P] = bis[2-(di-isopropylphosphino)phenyl]methane, iPr2P-C6H4-CH2-C6H4-PiPr2). Structural studies and DFT calculations indicate that the interaction between palladium and carbon is best described as a single bond, associated with nucleophilic character at that carbon atom. The characteristics of 3 were probed by reactions with electrophiles (MeI), acids (MeOH and HCl), and para-toluidine.