Reactivity of cyclopallatated compounds. III. Reaction with group V donor atoms ligands

Abstract In organic solvents, ligands such as pyridine, trialkyl and triarylphosphines, Triphenylarsine and stibine react quantitatively with cyclopalladated dimers of the type (Pd(CN)X) 2 (where CN = acetophenone hydazone) to give monomeric compounds of the type Pd(C-N)LX(X = Cl, Br, I). The presence of an excess of phosphine leads to Pd(C-N)L 2 X, in which the nitrogen is no longer coordinated. With bidentate ligands a new type of complexes is obtained: in which AA represents 1,2-bis(diphenylphosphino)ethane and 1,2-bis(diphenylarsino)ethane. With ethylenediamine (en), only the ionic complex [Pd(CN) en] + X − is formed. In aqueous solutions, cationic compounds of palladium can be isolated with pyridine or bidentate ligands. The stereochemistry of these complexes is discussed on the basis of v(PdX) infrared frequencies; N.M.R. data for the CN ligand are given.