An efficient oxidation of toluene over Co(II)TPP supported on chitosan using air

Abstract

An efficient oxidation of toluene to benzaldehyde and benzyl alcohol is accomplished over chitosan(CTS)-supported Co(II)TPP catalyst [Co(II)TPP/CTS] under a relatively mild reaction condition using air in absence of reductants and solvents, it can be reused for five times, with average selectivity of 65%, average toluene conversion of 8.83% and average turnover number of 69804.

Graphene-hemin hybrid material as effective catalyst for selective oxidation of primary C-H bond in toluene

“…In contrast, with protective support from GN, hemin seems to function well: H-GN yields appreciably higher conversion rate (9.42%) than hemin (1.02%) or GN (0.14%), or in absence of catalyst (0.22%) (Table 1, Entries 1–4). TON reaches 9,420 in 12 hours, which is comparable or even better than other reported catalysts (see Supplementary Table S5 for more comparison)444546. In addition, it can be observed H-GN gives slightly different product profile from other systems that selectivity towards BAC is more significant than BAD and BAL.…”

“…Furthermore, addition of halogen cocatalysts and acidic solvents makes it environmentally unfriendly. Earlier studies444546 have confirmed metalloporphyrin with or without support as active catalyst for this reaction. However, those results are either of relatively low yield, or from high temperature, high pressure condition, not mentioning the catalysts used are impractical to be synthesized in large quantity.…”

“…3a, b). The catalytic process can be separated into three stages354546: firstly, with initial addition of H-GN catalyst, oxygen donors from peroxide oxidize hemin and forms oxoiron(IV) species. This induction period is slow and products are mainly BAL and BAD.…”

Solvent-free liquid-phase selective catalytic oxidation of toluene to benzyl alcohol and benzaldehyde over CeO2–MnOx composite oxides

“…30 Huang et al prepared a chitosan (CTS)-supported Co( ii ) TPP catalyst, and 8.8% toluene conversion with 65.0% selectivity towards BAL and BOL was achieved. 31 However, the preparation procedure of the catalyst was complex and its cost was high in the above-mentioned processes. Therefore, it remains a grand challenge to construct an environmentally friendly and low-cost catalytic system that can achieve a high selectivity to BAL and BOL without solvents and other additives in the oxidation of toluene.…”

Highly Efficient Oxidation of Toluene to Benzoic Acid Catalyzed by Manganese Dioxide and N-Hydroxyphthalimide

“…However, the low catalytic activities and expensive solvents limited the application of these methods. The investigations of new technologies to improve this process still have attracted much attention so far [21,22].…”