DFT STUDIES ON THE STABILITY OF THE TRANS AND CIS ISOMERS IN THE SQUARE PLANAR PALLADIUM(II) COMPLEXES Pd(I)(PPh3) (η3-XCHC(Ph) CHR) (X = CMe3, CO2 Me, P(O)(OMe)2, AND SO2H; R = H, Me)

The relative stability of the trans and cis isomers in the square planar palladium(II) complexes Pd(I)(PPh3)(eta(3)-XCHC(Ph) CHR) (X = H, Me, CMe3, CO2Me, P(O)(OMe)(2), and SO2H; R = H, Me) was investigated with the aid of the B3LYP density functional theory calculations. We examined how the substituents X, with different electronic properties, of the eta(3)-allyl ligands affect the relative stability of the trans and cis isomers. Through the investigation, we were able to explain the trans/cis relative stability derived from the experimentally measured trans/cis isomer ratios in the palladium(II) complexes.