Cyclopalladates of 1-(2′-hydroxynaphthylazo) naphthalene complexes: Oxygen insertion into the Palladium-Carbon (Naphthyl) bond

Abstract

High yield regiospecific metaloxylation (M-C → M-OC) of the Pd-C (Naphthyl) bond of palladium (II) complexes [Pd(L)(D)], 1a and 2a, (D = 4-picoline and PPh3 respectively), of the ligand H2L [1-(2′-hydroxynaphthylazo)naphthalene] by m-chloroperbenzoic acid (m-CPBA) at room temperature in dichloromethane medium have been described. The metaloxylated palladium (II) complexes (1c and 2c) have been characterized by spectroscopic techniques. The catalytic oxygen insertion into the Pd-C (naphthyl) bond of the cyclopalladates has also been achieved at room temperature in presence of iron (III) porphyrin catalyst, F20TPPFe (III) Cl [F20TPP: meso-5,10,15,20-tetrakis (Pentafluorophenyl) porphinato dianion] using mild hydrogen peroxide (H2O2) as terminal oxidant. Solvent effects in the catalytic metaloxylation reactions have also been examined and reported.