Novel Manganese Complex as an Efficient Catalyst for the Isobutyraldehyde-Mediated Epoxidation of Cyclic Alkenes with Dioxygen

Abstract

Abstract:The highly efficient oxidation of cyclic alkenes was realized using a novel manganese complex as catalyst and molecular oxygen as oxidant in the presence of isobutyraldehyde. The reaction of 2-pyridinecarboxylic acid with p-toluidine gave the corresponding amide in good yield. A manganese complex bearing this ligand was highly active in isobutyraldehyde-mediated epoxidation of cyclic alkenes using molecular oxygen as oxidant, and up to and over 99.9% conversion of the substrate and 99% yield of the epoxide were obtained for the epoxidation of norbornylene.

Epoxidation of cycloalkenes with cobalt(II)-exchanged zeolite X catalysts using molecular oxygen

“…Transition metal complexes of Co, Ti, Mn, Mo, were used as the catalyst, and high selectivity of epoxides of cyclic olefin such as cyclohexene has been reported [28][29][30][31][32]. Among all, cobalt complexes have been extensively used for the epoxidation of various alkene substrates with different oxidants [33][34][35].…”

Optimizing the Synthetic Potential of O2: Implications of Overpotential in Homogeneous Aerobic Oxidation Catalysis

“…88,89 In the early 1990s, Mukaiyama and co-workers reported Nicatalyzed epoxidation of substituted alkenes with O 2 , using an aldehyde as a sacrificial reductant (Figure 8A), 83,84 and analogous reactivity was reported with Mn-and Fe-based catalysts. 90,91 Subsequent mechanistic studies showed that the Ni catalyst initiates aldehyde autoxidation to generate an acylperoxyl radical, which adds to the alkene and then undergoes O atom transfer from the alkylated peracyl intermediate. 92 A peracid can also form under the reaction conditions and mediate epoxidation of the alkene substrate (Prilezhaev reaction).…”

Modified Ti-MWW Zeolite as a Highly Efficient Catalyst for the Cyclopentene Epoxidation Reaction

“…Cyclopentene has been reported to be epoxidized by oxygen, hydrogen peroxide (H 2 O 2 ), or organic peroxide, producing 1,2epoxycyclopentane (Pramanik et al, 2007;Aleksandra, 2008;Maiti et al, 2008). However, the process using oxygen as the oxidant generally requires the addition of isobutyraldehyde and other co-oxidants to obtain a high yield (Qi et al, 2005;Mekrattanechai et al, 2018). In addition, the reaction system is too complex and difficult to control.…”