Magnetic nanoparticles supported binuclear manganese(ll) complex via covalent interaction: A highly efficient and reusable catalyst for the epoxidation of cyclohexene

摘要

In the present work, the highly efficient epoxidation of cyclohexene catalyzed by Fe_3O_4@SiO_2/([Mn_2L(HL)(H_2O)_4], is reported. First, the Fe_3O_4@SiO_2 nanoparticles were modified with (3-chloropropyl)-trimethoxysilane (CPTMS) group and then [Mn_2L(HL)_2(H_2O)_4] was attached to the support via covalent linkages. The prepared catalyst was characterized by spectroscopic studies and chemical analyses. This catalytic system serves as catalyst for the oxidation of cyclohexene to cyclohexene epoxide and 2-cyclohexene-l-ol using H_2O_2 as an oxidant. Thus, this catalytic system shows high activity and selectivity toward cyclohexene epoxide. Also activity of the immobilized catalyst remains nearly unchanged after five cycles, that it is truly heterogeneous.