Mn(II)-substituted polyoxophosmolybdate supported on the amino-functionalized SBA-15 as catalyst for epoxidation reactions

Ordered mesoporous SBA-15 materials present a series of some unique properties which recommend them as ideal host structures. These properties include an improved framework cross-linking and thick walls, high (hydro)thermal stability, large specific surface areas, well-defined dual pore structures composed of hexagonal arrays of large and tunable primary cylindrical mesopores, and also secondary (ultra) supermicropores or small mesopores [1‒3]. Therefore, SBA-15 is suitable for successful anchoring platform materials for various kinds of catalysts [4, 5]. As the difficulty in separation and reuse of homogenous catalysts from the reaction medium, hamper their commercial applications, preparing the heterogeneous catalysts via immobilization of the catalytically active species onto/into the surface of traditional solid supports, has hence attracted a lot of attention [6]. Olefins epoxidation is an important reaction in the production of a wide variety of valuable materials used laboratorial and also industrial processes [7, 8]. As a result, enormous efforts have gone into designing and fabrication of suitable catalysts with high selectivity, stability and recyclability. Herein, we report a simple method for grafting of the homogeneous Mn(II)-substituted phosphomolybdenum moiety on the amino-functionalized SBA-15 (Scheme 1). The synthesized nanomaterials, SBA–MnPOM have been identified by a series of characterization techniques. The catalytic properties of the nanocatalyst were investigated in the epoxidation of olefins using TBHP as oxygen source which exhibited excellent catalytic performance with high yields and selectivity.