A New Nitrogen Pd(II) Complex Immobilized on Magnetic Mesoporous Silica: A Retrievable Catalyst for C-C Bond Formation

A new nitrogen ligand, i.e. 1,3-di-(o-aminophenoxy)-2-propyl propargyl ether (DPPE), has been synthesized and characterized. Magnetic mesoporous silica composite (MNP@SiO2-SBA) was obtained via embedding magnetite nano-particles (MNPs) between SBA-15 channels. DPPE palladium dichloride (MNP@SiO2-SBA-DPPE-Pd(II)) was then prepared via click chemistry and fully characterized. The activity and recyclability of supported magnetic Pd(II) catalyst were evaluated in Heck coupling reaction after optimizing the optimal reaction conditions including solvent, amount of catalyst, base and temperature. Aryl iodides and aryl bromides showed enhanced activity compared to those of aryl chlorides in the Heck reaction. The catalyst was easily separated magnetically, reused in five runs sequentially, and no significant loss of activity was observed.

Automated summary

A new nitrogen ligand DPPE was synthesized and used to prepare a magnetic Pd(II) catalyst MNP@SiO2-SBA-DPPE-Pd(II), which showed good activity and recyclability in the Heck coupling reaction. Aryl iodides and aryl bromides exhibited higher activity compared to aryl chlorides with this catalyst.