2-Hydroxyethyl-Substituted Pd-PEPPSI Complexes: Synthesis, Characterization and the Catalytic Activity in the Suzuki-Miyaura Reaction for Aryl Chlorides in Aqueous Media

In recent years, PEPPSI (Pyridine-Enhanced Precatalyst Preparation Stabilization and Initiation) complexes have attracted attention in organometallic chemistry. This study contains the synthesis of the 2-hydroxyethyl-substituted Pd-PEPPSI complexes and their catalytic activity in the Suzuki-Miyaura reaction aryl chlorides in aqueous media. The Pd-PEPPSI complexes have been prepared from the 2- hydroxyethyl-substituted N-heterocyclic carbene (NHC) precursors, palladium chloride and 3-chloropyridine. The Pd-PEPPSI complexes have been characterized by using (HNMR)-H-1, (CNMR)-C-13, FTIR spectroscopy and elemental analysis techniques. The Pd-PEPPSI complexes have been examined as catalysts in the Suzuki-Miyaura reactions in aqueous media with arylboronic acid derivatives. Also, they have demonstrated excellent activity in these reactions. Molecular and crystal structure of one of the 2-hydroxyethyl substituted Pd-PEPPSI complex was determined by single crystal X-ray diffraction method. X-ray studies show that the molecular structure adopts a slightly distorted square-planar geometry with the palladium (II) center.