An air stable and efficient palladium catalyst for Suzuki-Miyaura cross coupling reaction at room temperature

The cross-coupling reaction between phenylboronic acid and various types of aryl halides (Suzuki reaction) was carried out using a catalytic amount of a new palladium catalyst (1-benzyl-3-(1-benzyl-1-methylpyrrolidin-1-ium-2-yl) pyridin-1-ium palladium chloride [DBNT][PdCl4]) in poly (ethylene glycol) (PEG-200) in the presence of KOH as the base. This new catalyst was synthesized and characterized by elemental analysis, NMR spectroscopy, UV–visible, and FT-IR spectra. This palladium catalyst is not sensitive to air and moisture, so reactions were carried out without using inert atmosphere at room temperature. The steric and electronic properties of the different substrates had a significant influence on the reaction conditions. This method for the synthesis of biarlys has several key advantages, including mild, environmentally friendly, and phosphine-free reaction conditions, excellent conversions as well as good to excellent yields, facile work-up.