Selective epoxidation of linear terminal olefins with metalloporphyrins under mild conditions

Abstract

The epoxidation of linear terminal olefins with metalloporphyrins in the presence of dioxygen and isobutyraldehyde under ambient temperature and atmospheric pressure was investigated. The results show that all olefins could be smoothly converted to epoxides with high selectivities (70%-90%). For the metalloporphyrins with different catalytic activities within 1-hexene epoxidation in the order of Fe > Mn > Co, T(o-Cl)PPFe(III)Cl was most effective, with a 41.7% yield and 80.2% selectivity of 1,2-epoxyhexane. Various amounts of catalyst were investigated, and it was found that with only 10 ppm catalyst the yield of 1,2-epoxyhexane and turnover number (TON) could reach up to 41.9% and 41859, respectively.

A practical innovative method for highly selective oxidation of alkenes and alkanes using Fe (III) and Mn (III) porphyrins supported onto multi‐wall carbon nanotubes as reusable heterogeneous catalysts

“…[33,34] In several reports on the catalytic epoxidation with molecular oxygen, high temperatures or extremely long reaction times have been evaluated to activate the triplet dioxygen. [21,35,36] Because the stoichiometry of oxygenation requires two electrons and two protons to reduce the second oxygen atom of dioxygen to water, the majority of reports mentioned an electron source such as borohydride, hydrogen and colloidal platinum, zinc powder, electrons from an electrode or aldehyde as reductant. These materials will gently moderate the reaction condition.…”

Olefins oxidation with molecular O2 in the presence of chiral Mn (III) salen complex supported on magnetic CoFe2O4@SiO2@CPTMS

“…Recently, selective oxidation of terminal alkenes is investigated. Usually, the catalytic epoxidation are carried out with toxic oxidants at high temperature and extremely long reaction time . Therefore, proposing a strategy to conduct the reactions using a nontoxic oxidant and short reaction in room temperature which also saves energy is desirable.…”

“…Usually, the catalytic epoxidation are carried out with toxic oxidants at high temperature and extremely long reaction time. [8][9][10] Therefore, proposing a strategy to conduct the reactions using a nontoxic oxidant and short reaction in room temperature which also saves energy is desirable. On the other hand, metal salen complexes and especially Mn (III) salen complexes could be used for the asymmetric epoxidation of olefins.…”