Selective liquid phase oxidation of toluene with air

Design and Development of New Carbon-Based Sorbent Systems for an Effective Containment of Hydrogen

“…While it is tempting to propose that this is due to an increased aromatic stabilization energy (e.g., pyridine vs. benzene), such a contrast is not supported from a review of the relevant literature. 24 As suggested by Crabtree et al 16 the favorable effect of incorporating nitrogen more likely stems from the well-known weakening of the C-H bonds of carbon atoms which are adjacent to nitrogen in the organic amines [25][26][27] , thus facilitating the overall dehydrogenation of the molecule. This reduction in C-H bond dissociation energy (BDE)…”

“…The carbon atom of the hydrocarbon group that is immediately adjacent to the aromatic moiety (e.g., a benzyl carbon) is considered to be "activated" towards chemical reactivity, including oxidation, vis-a-vis the carbon atom of a saturated hydrocarbon molecule. Oxidation of activated hydrocarbon functional groups, such as the side chain groups on aromatic molecules (e.g., toluene as in 1a, 1b, 1c in Table 9-1) can be accomplished, using air as the oxidant, with nanoporous molecular sieves 15 and by cobalt tetraphenylporphyrin catalysts 16 . A catalytic air oxidation of diphenylmethane to benzophenone using air as the oxidant over alumina-supported NaF and KF catalysts has been reported.…”

Biomimetic Oxidation of Hydrocarbons with Air over Metalloporphyrins

“…Further researching for the selective catalysis of metalloporphyrins for the aerobic oxidation of different C-H bonds of hydrocarbons in the system of manganeseporphyrinmethylcyclohexane-air was investigated in detail in our group(Scheme 4) [61]. After systematic investigation, it showed that the oxidation reaction of alkanes catalyzed by metalloporphyrin is kept to the classic radical chain mechanism [62][63][64]. While at the initial stage of methylcyclohexane aerobic oxidation, metalloporphyrin turns into high-valent oxometal radical cation [PM IV =O] •+ , which is responsible for the velocity of the reaction.…”

“…But these technologies are companied by drawbacks such as low selectivity and use of large amounts of solvents and bromides [80]. We [81] firstly reported catalysis of simple cobalt tetraphenylporphyrin for selective liquid phase oxidation of toluene with air in the absence of any solvents or promoters to produce benzaldehyde and benzyl alcohol(Scheme 8).…”

Solvent-Free Selective Oxidation of Toluene with O2 Catalyzed by Metal Cation Modified LDHs and Mixed Oxides

“…Among all the processes of selective oxidation of toluene, the liquid phase oxidation process with O 2 , especially in the absence of organic solvent, was eye-catching due to the "green" and mild reaction conditions as well as high selectivity to object product, and various catalytic systems have been reported [5][6][7][8][9][10][11][12]. Xu et al used CuFe/γ-Al 2 O 3 to the selective oxidation of toluene with O 2 , and the 7.4% of toluene conversion and 46.5% of selectivity to benzyldehy were obtained [5].…”