Abstract
Ferrocene P,N-ligands have been extensively studied due to their favorable catalytic properties. This contribution focuses on a pair of new, isomeric ferrocene phosphinoamines, FcNHCH2CH2PPh2 (1) and FcN(Me)CH2PPh2 (2), which were prepared from aminoferrocene, converted to the respective phos-phine selenides (1-Se and 2-Se) and further studied as ligands in Pd(II) complexes containing the 2-(dimethylamino-κN)phenyl-κC(1) auxiliary (L(NC)) ligand.
Thus, cleavage of the dimeric precursor [(L(NC))Pd(μ-Cl)]2 with the phosphinoamines afforded the corresponding phosphine complexes [(L(NC))PdCl(1-κP)] (5) and [(L(NC))PdCl(2-κP)] (6) with trans-P,N configuration. The subsequent removal of the chloride ligand with AgClO4 from 5 produced the cationic bis-chelate complex [(L(NC))PdCl(1-κ(2)P,N)]ClO4 (7), whereas an analogous reaction with 6 gave no defined product.
The phosphinoamines and their complexes were char-acterized by elemental analysis and common spectroscopic methods, and the crystal structures of 1, 2 , and 7 were determined by single-crystal X-ray diffraction analysis. A cyclic voltammetry study, supported by DFT calculations, revealed that the primary electrochemical oxidation of these compounds occurs at the ferrocene unit.