Magnetic nano-reactors with high regioselectivity

ORGN 551

Chuansong Duanmu, chuansongduanmu@yahoo.com, Philip Stevens, stevensphilip@yahoo.com, Yan Zheng, tjuzhengyan@hotmail.com, and Yong Gao, ygao@chem.siu.edu. Department of Chemistry and Biochemistry, Southern Illinois University, 224 Neckers Hall, Carbondale, IL 62901
Our group has investigated the use of dendron-coated maghemite nanoparticles as magnetically recoverable reactors for promoting C-C formations with high regio-selectivity. A 12 nm-sized maghemite nanocrystals were coated with Simanek(melamine)-type dendrons and a Pd catalyst. The dendron molecules served as a “gate” for controlling the accessibility of the reagents towards the surface-immobilized Pd catalyst. By varying the generation of dendron ligands, the ratio of dendron/Pd catalyst, and the size of the nanoparticle core, we could tune up the selectivity of our nano-reactors towards Suzuki cross-coupling reactions. In addition, we were able to recover such magnetic nano-reactors via magnetic concentration for repeated uses.