An active and recyclable bicontinuous cubic Ia3d mesostructural Rh(I) organometal catalyst for 1,4-conjugate addition reaction in aqueous medium

摘要

An active and reusable heterogeneous Rh(I) organometal catalyst (Rh(I)-PMO-3D) was synthesized by template-directed co-condensation of Rh[PPh2(CH2)2Si(OCH2CH3)3]3Cl and (CH3CH2O)3SiPhSi(OCH2CH3)3. This catalyst displayed bicontinuous cubic Ia3d mesostructure channel, which ensured the high dispersion of Rh(I) active sites and the convenient diffusion of reactant molecules into the pore channels. Meanwhile, the Ph-functionalization could enhance the surface hydrophobicity, which promoted the adsorption of organic reactant molecules on the catalyst, especially in aqueous medium. During water-medium 1,4-conjugate addition reactions, Rh(I)-PMO-3D catalyst exhibits higher catalytic activity than the corresponding homogeneous Rh(I) catalyst and could be used repetitively for more than five times, showing a good potential in industrial applications.