The catalytic efficiency of Fe–porphyrins supported on multi-walled carbon nanotubes in the oxidation of olefins and sulfides with molecular oxygen

In the present study, CoFe2O4@SiO2@CPTMS nanocomposite was synthesized and the homogeneous chiral Mn‐salen complex was anchored covalently onto the surface of CoFe2O4@SiO2@CPTMS nanocomposite. The heterogeneous Mn‐salen magnetic nanocatalyst (CoFe2O4@SiO2@CPTMS@ chiral Mn (III) Complex) was characterized by different techniques including transmission electron microscopy (TEM), Fourier transform infrared (FT‐IR), vibrating sample magnetometer (VSM), scanning electron microscopy (SEM), powder X‐ray diffraction (XRD) and thermogravimetric analysis (TGA). Then, the aerobic enantioselective oxidation of olefins to the corresponding epoxide was investigated in the presence of magnetic chiral CoFe2O4@SiO2@Mn (III) complex at ambient conditions within 90 min. The results showed the corresponding products were synthesized with excellent yields and selectivity. In addition, the heterogeneous CoFe2O4@SiO2@ CPTMS@ chiral Mn (III) complex has benefits such as high selectivity and comparable catalytic reactivity with its homogeneous analog as well as mild reaction condition, facile recovery, and recycling of the heterogeneous catalyst.

Section: Resultsmentioning

confidence: 86%

“…respectively. [28] The XRD pattern of the CoFe 2 O 4 @SiO 2 spheres has a broaden peak in the 2θ range of 20-30 o which results from the amorphous silica.…”

Section: Preparation and Characterization Of Magnetic Chiral Mn (Iimentioning

confidence: 98%

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

Hemmat

Nasseri

Allahresani

2019

“…Multi‐walled carbon nanotubes (MWCNTs) with functional groups are one of the recommended solid supports for immobilization of metal complexes due to their unique structural, mechanical, thermal and electronical properties along with high surface area and insolubility in most solvents . In the recent works in our group, the [Fe (THPP)Cl] immobilized onto functionalized MWCNTs has proven to be an excellent catalyst for the epoxidation of olefins in the presence of molecular oxygen and isobutylaldehyde …”

Section: Introductionmentioning

confidence: 99%

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

Rayati

Nafarieh

2019

Self Cite

Functionalized multi‐walled carbon nanotubes were used for covalent immobilization of meso‐tetrakis(4‐carboxyphenyl) porphyrinatoiron (III) chloride [Fe (TCPP)Cl] and meso‐tetrakis(4‐carboxyphenyl) porphyrinatomanganese (III) acetate [Mn (TCPP)OAc]. The full characterization of the hybrid porphyrinic nanomaterials, by Fourier transform‐infrared and UV–Vis spectroscopy, transmission electron microscopy, thermogravimetry and flame atomic absorption spectrometry is described. The oxidation of alkenes and alkanes with molecular oxygen as green oxidant in the presence of Mn‐ and Fe‐catalysts has been studied in a comparative manner. The Fe‐catalyst was shown to have higher catalytic activity compared with the Mn‐catalyst. In addition, both separable solid catalysts can be recovered and reused at least 10 times along with good yields.

“…Metal catalyzed oxidation of olefins constitutes an important area in modern chemistry from the academic and industrial point of view . Among transition metal complexes which provide a convenient route for oxygen transfer processes, Schiff base complexes have been found to be very effective homogeneous catalysts for the selective oxidation reactions .…”

Section: Introductionmentioning

confidence: 99%

Synthesis and characterization of molybdenum (VI) complex immobilized on polymeric Schiff base‐coated magnetic nanoparticles as an efficient and retrievable nanocatalyst in olefin epoxidation reactions

Mortazavi-Manesh

Bagherzadeh

2019

In this study, a new polymeric functionalized magnetic nanocatalyst containing a molybdenum Schiff base complex was prepared using a few consecutive steps. Poly (methylacrylate)‐coated magnetic nanoparticles were synthesized via radical polymerization of methyl acrylate onto modified magnetic nanoparticles followed by the amidation of the methyl ester groups with hydrazine. Polymeric functionalization efficiently provides the advantage that more catalytic units can be grafted on the surface of magnetic nanoparticles. The functionalization process was continued with salicylaldehyde which introduced Schiff base groups on to the surface of the polymeric support. In the final step, the desired catalytic system was prepared via complexation of the Schiff base groups with MoO2(acac)2. The resulting nanoparticles were characterized by infrared spectroscopy, powder X‐ray diffraction, scanning and transmission electron microscopy, elemental analysis, inductively coupled plasma optical emission spectrometry, vibrating sample magnetometry and thermogravimetric analysis. This heterogenized catalytic system was also found to be highly active, sustainable and recyclable nanocatalyst in alkene epoxidation. Eventually, the attractive features of the synthesized catalyst such as simple work‐up, good stability, magnetic separation, high TOF and high surface area; make it appropriate for oxidation reactions.