Catalytic properties of N-hydroxyphthalimide immobilized on a novel porous organic polymer in the oxidation of toluene by molecular oxygen

Abstract

A novel porous organic polymer pSt was prepared based on silica gel and used for the immobilization of NHPI. The obtained heterogeneous catalyst could adsorb toluene and oxidize it to benzoic acid using a co-catalyst Co(OAc)2 and molecular oxygen.

N‐Hydroxyphthalimide Anchored on Diamond Nanoparticles as a Selective Heterogeneous Metal‐free Oxidation Catalyst of Benzylic Hydrocarbons and Cyclic Alkenes by Molecular O2

“…A few years ago, we reported the catalytic activity of NHPI adsorbed on porous metal organic frameworks (MOFs), in where there is a synergism between the adsorbed NHPI and the metal nodes of the MOF . In other reports, NHPI derivatives have been anchored to polymers, based on polystyrene or acrylates, and used to promote oxidations of benzylic hydrocarbons in combination or in the absence of Co 2+ ions. NHPI derivatives have also been anchored on mesoporous silica again using Co 2+ salts as promoter …”

Selective Aerobic Oxidation of P-Methoxytoluene by Co(II)-Promoted NHPI Incorporated into Cross-Linked Copolymer Structure

“…As shown in Scheme 2, the reaction proceeds with the formation of three major products, i.e., 4-methoxybenzyl alcohol (p-anisyl alcohol), 4-methoxybenzaldehyde (p-anisaldehyde), and 4-methoxybenzoic acid (p-anisic acid). In the catalytic tests, we used conditions that allow relatively easy comparison of the results obtained in the presence of NHPI-containing catalysts with the literature data, e.g., [20,47,48]. Furthermore, the temperature of 80 • C was selected to achieve the optimal reaction rate.…”

Lipophilic N‐Hydroxyimide Derivatives: Design, Synthesis, and Application to Aerobic Alkane Oxidation Under Neat Conditions

“…A possible decomposition route of the reactive intermediate, phthalimide-N-oxyl radical (PINO), is the ring-opening of imide moiety, which was proposed by Masui and coworkers based on mass spectrometric analysis of decomposition products (Figure 1b). [24] While heterogeneous support, [25][26][27][28][29][30][31][32] use of ionic liquid, [33][34][35][36][37] phase-transfer conditions, [38,39] supercritical CO 2 , [40] combination with other redox mediators, [41][42][43] and the combination of these techniques [37] have been suggested to address the lifetime issue, NHPI derivatives with intrinsic long lifetime are highly desirable. For aerobic oxidation of hydrocarbons, one of the examples superior to NHPI is lipophilic NHPI A reported by Ishii and coworkers (Figure 2a).…”