Pd–H elimination reactions in palladium(ii) allylic complexes

Abstract

The ease of H elimination from the 4- (β-) position in a series of allylic complexes [Pd(5-C₆F₅-1-3-η³-cyclohexenyl)XL]ⁿ⁺ (X, L = Br, N-, P-donor, C₆Cl₂F₃; n = −1, 0, +1) was compared by analyzing their decomposition products at 50 °C. Pd–H elimination does not occur for cationic complexes, whereas it is the main decomposition pathway for neutral and anionic complexes. In addition to the charge of the complex, the ease of this Pd–H elimination is determined by the trans influence of the ligands (aryl > PMe₃ > Br, N-donor).