Preparation, characterization, and catalytic performance of copper content SBA-15 in the synthesis of aryl ethers

Ullmann coupling reactions of aryl bromides/iodides and phenols is one of the two major methods for the synthesis of aryl ether applied in various natural products, biological compounds, pharmaceutical and polymer industries [1]. SBA-15, a family of mesoporous silica materials with hexagonal arrangement attracted more attention, because of the significant hydrothermal and mechanical stability, which is as high as, or even more than those with cubical arrangement MCM-41 [2]. On the other hand, functionalized SBA-15 supports have been proved as promising materials for loading different nanoparticles or metal particles, which provide heterogeneous catalyst [3]. In the present work, a simple route has been developed to load copper(II) species onto the diamine-functionalized pore surface of SBA-15 using aqueous solution of copper(II) acetate (Cu(OAc)2) as the Cu sources, without pore blocking and without destroying its ordered mesostructure. The catalyst showed high activity for the o-arylation reaction between aryl halides and various substituted phenols, under mild reaction conditions. It could be easily separated from the reaction mixture, by simple filtration and reused several times without a significant loss in activity. We have obtained diaryl ethers in a yield as high as calculated 95%.

Keywords:

SBA-15 , O-arylation , Hydrothermal , Aryl halide , Mesoporous