Insights into the Aryl-Aryl Exchange between Palladium and Phosphane Ligands in Pd(II) Complexes: Preparation of Phthalocyanine-Containing Phosphonium Salts This work was supported by CICYT (Spain) through grant MAT-99-0180. We are indebted to Mr. G. Martin Fuchs, Laboratoire de Photonique Quantique et Moléculaire, Ecole Normale Supérieure de Cachan, France, for the NLO measurements.