Organometallic-polyoxometalate hybrid based on V-Schiff base and phosphovanadomolybdate as a highly effective heterogenous catalyst for hydroxylation of benzene

•A novel organometallic-polyoxometalate hybrid is prepared.•The hybrid catalyst leads to the heterogeneous hydroxylation of benzene with H2O2.•The hybrid catalyst gives high conversion and selectivity.•The catalyst can be easily recovered and reused.

A novel organometallic-polyoxometalate hybrid has been prepared by anion-exchange of V Schiff base functionalized ionic liquid with V-containing Keggin-type polyoxometalate. The hybrid solid with two types of catalytic active V components demonstrates remarkable capability for heterogeneous hydroxylation of benzene with excellent phenol yield 19.6% and 100% selectivity. After reaction, the catalyst can be simply recovered by filtration and reused at least 4 times without the change of catalyst structure. The synergistic effect between metal Schiff base complex and polyoxometalate plays an important role in the promotion of catalytic activity.

Graphical abstractA new organometallic-polyoxometalate hybrid is synthesized and proved to be a highly efficient and steadily reused heterogeneous catalyst for hydroxylation of benzene with H2O2.Figure optionsDownload full-size imageDownload as PowerPoint slide