A highly active palladium(II)–bis(oxazoline) catalyst for Suzuki–Miyaura, Mizoroki–Heck and sonogashira coupling reactions in aqueous dimethylformamide
Résumé
An efficient catalytic system based on a new palladium–bis(oxazoline) () complex has been developed. The complex adopts a legless chair-type structure where the distorted square planar [PdN2Cl2] moiety and the benzene ring spacer represent the seat and the chair back, respectively. The catalytic activity of has been investigated in dimethylformamide–water under aerobic and mild conditions in Suzuki–Miyaura coupling reactions of arylboronic acids with aryl iodides, aryl bromides and aryl chlorides, Mizoroki–Heck coupling reactions of aryl halides with styrene derivatives, and Sonogashira coupling reactions of aryl halides with terminal alkynes. A wide range of functional groups as substituents on the arylboronic acids and aryl halides were considered. demonstrates exceptional air and moisture stability. Of note, the catalyst system based on shows high recycling ability in Suzuki–Miyaura coupling reactions in dimethylformamide–water without any loss in catalytic activity. Copyright © 2015 John Wiley & Sons, Ltd