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

Abstract

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.

Synthesis and application of CoFe₂O₄@THAM@PHG‐SO₃H nanoparticles as a new and highly recyclable nanocatalyst in the one‐pot multicomponent synthesis of 3,4‐dihydropyranochromenes and chromeno[3,4‐b]quinoline‐6‐ones

“…[7][8][9][10] Previous studies in the field of CoFe₂O4 magnetic cores have reported the synthesis of various MNPs, such as CoFe₂O₄@SiO₂@CPTMS, 11 CoFe₂O₄@SiO₂-Pta, 12 CoFe₂O₄@SiO₂-SO3H, 13 CoFe₂O₄@Pr, 14 and CoFe₂O₄@asparagine-Cu/Ni. 15 Acidic-functionalized catalysts have gained importance in a variety of organic transformations for the rapid synthesis of heterocycles. [16][17][18][19] More than 90% of newly synthesized drugs have heterocyclic compounds as their core.…”

Cobalt ferrite magnetic nanoceramics as an efficient nanocatalyst for the oxidation of olefins in the presence of molecular O2 as an environmentally safe oxidant

“…The selective oxidation reaction with a lowtoxicity oxidant is significant and of particular importance from the point of view of green chemistry. 16 For this reason, non-toxic and green oxidants such as H 2 O 2 and O 2 have been proposed in the catalytic oxidation systems. 17 Fast kinetics, high content of active oxygen, low cost, and absence of by-products are some of the advantages of molecular O 2 , which is why it has been widespread.…”

“…Therefore, in the last few years, the effective development of selective oxidation methods of olefins has received much attention. The selective oxidation reaction with a low‐toxicity oxidant is significant and of particular importance from the point of view of green chemistry 16 . For this reason, non‐toxic and green oxidants such as H 2 O 2 and O 2 have been proposed in the catalytic oxidation systems 17 .…”

Synthesis, characterization, and application of CoFe2O4@amino‐2‐naphthol‐4‐sulfonic acid as a novel and reusable catalyst for the synthesis of spirochromene derivatives

“…[11] Some MNPs that used in catalytic applications include iron oxide (Fe 3 O 4 ), cobalt ferrite (Fe 2 CoO 4 ), maghemite ( γ -Fe 2 O 3 ), and zinc ferrite (ZnFe 2 O 4 ). [12][13][14][15] Today, great attention has been paid to cobalt ferrite (CoFe 2 O 4 ) nanocrystals with spinel structure due to their superior characteristics, such as high saturation magnetization, large surface area-tovolume ratio, and shape-dependent magnetic behavior. [16][17][18][19][20][21][22] As a review of previous studies, many functionalized CoFe 2 O 4 MNPs have been reported as a heterogeneous catalyst in multicomponent reactions (MCRs) such as CoFe 2 O 4 @SiO 2 @CPTMS, [13] CoFe 2 O 4 @SiO 2 -SO 3 H, [23] CoFe 2 O 4 @SiO 2 -PTA, [24] CoFe 2 O 4 /TMU-17-NH 2 , [25] CoFe 2 O 4 @l-asparagine-Cu/ Ni, [26] CoFe 2 O 4 @glycine-M, [27] CoFe 2 O 4 @Pr.…”