Synfacts 2006(5): 0515-0515  
DOI: 10.1055/s-2006-934386
Polymer-Supported Synthesis
© Georg Thieme Verlag Stuttgart · New York

Polymer-Incarcerated Palladium-Catalyzed Suzuki and Heck Reactions

Contributor(s): Yasuhiro Uozumi, Yoichi M. A. Yamada
H. Hagio, M. Sugiura, S. Kobayashi*
The University of Tokyo, Japan
Further Information

Publication History

Publication Date:
21 April 2006 (online)

Significance

A polymer-incarcerated (PI) palla­dium catalyst was practically prepared from Pd(NO3)2 and a polystyrene-based copolymer 1 with NaOAc under reducing conditions. Thus, when a solution of 1 with those reagents was heated for three hours, a polymer-supported palladium was successfully formed, which was coacervated with hexane and crosslinked to give PI Pd. In the presence of 5 mol% Pd of PI Pd catalyst, the Mizorogi-Heck reaction of PhI with ethyl acrylate and K2CO3 in NMP was performed to afford ethyl cinnamate in 94% yield. The Suzuki-Miyaura couplings of aryl bromides or 4-acetyl chlorobenzene with arylboronic acids (1.5 equiv) were also examined to give biphenyl derivatives in 95% quantitative yields (8 examples). The PI Pd catalyst was recyclable two times for these reactions.