Design and synthesis of bi-functional Co-containing zeolite ETS-10 catalyst with high activity in the oxidative coupling of alkenes with aldehydes for preparing α,β-epoxy ketones

Abstract

Developing highly efficient heterogeneous catalysts for organic synthesis is of great importance in modern synthetic chemistry. In this work, Co (or Ni)-containing mesoporous zeolite ETS-10 (Co-METS-10 and Ni-METS-10) with both metal and strong basic sites were synthesized and applied for the direct oxidative coupling of alkenes with benzaldehydes to synthesize α,β-epoxy ketones. Co (or Ni)-METS-10 catalysts show high activity and product selectivity, as compared to metal-free mesoporous zeolite ETS-10 (METS-10). This feature is attributed to the fact that the highly dispersed Co (or Ni) species could facilitate the tert-butyl hydroperoxide transformation into more alkyloxy and alkylperoxy radicals, which triggers the alkenes undergoing radical addition with aldehyde and alkylperoxy to form β-peroxy ketones. Meanwhile, the basic sites on Co (or Ni)-METS-10 catalysts benefit the formation of α,β-epoxy ketone from β-peroxy ketone.