Polystyrene‐Supported PPh<sub>3</sub> in Monolithic Porous Material: Effect of Cross‐Linking Degree on Coordination Mode and Catalytic Activity in Pd‐Catalyzed C−C Cross‐Coupling of Aryl Chlorides
Hikaru Matsumoto, Yu Hoshino, Tomohiro Iwai, Masaya Sawamura, Yoshiko Miura
Abstract
Abstract Hybridization of porous synthetic polymer and sophisticated ligands play an important role in transition‐metal catalysis for chemical transformations at laboratory and industrial levels. A monolithic porous polymer, which is a single piece with continuous macropores, is desired for high permeability, fast mass transfer properties, high stability, and easy modification. Herein, we first develop a monolithic porous polystyrene containing three‐fold cross‐linked PPh 3 ( M‐PS‐TPP ) for transition‐metal catalysis. The monolithic and macroporous structure of M‐PS‐TPP was fabricated via polymerization‐induced phase separation using porogenic solvent. Moreover, the M‐PS‐TPP was synthesized using different feed ratios of divinylbenzene (DVB) for site‐isolation and mono‐P‐ligating behavior of PPh 3 . 31 P CP/MAS NMR analysis revealed that the different selectivity of M‐PS‐TPP s was obtained in formation of mono‐P‐ligation toward Pd II . The macroporous properties and controlled mono‐P‐ligating behavior of M‐PS‐TPP facilitated the challenging Pd‐catalyzed Suzuki‐Miyaura cross‐coupling reaction of chloroarenes.