4,4'-(4,4'-Isopropylidenediphenoxy)bis(N-hydroxyphthalimide), which is a new lipophilic analogue of N-hydroxyphthalimide, can act as an effective catalyst in the aerobic oxidation of alkylaromatics under reduced amounts of polar cosolvent. The catalyst was selected on the basis of an in-depth study of the influence that substituents on the aromatic ring of N-hydroxyphthalimide exert on determining the NO-H bond dissociation energy (BDE). BDE values for a range of model molecules are calculated by DFT and measured by EPR spectroscopy. The new catalyst can be successfully employed in the aerobic oxidation of cumene, ethylbenzene, and cyclohexylbenzene, affording, in all cases, good conversions and high selectivity for the corresponding hydroperoxide. The effect of solvent, catalyst, and temperature has also been investigated.

Host–guest complexation of α,ω-dibromides showed rabid tumbling conformation on NMR timescales and afforded mono hydroxyl bromides after hydrolysis in D2O.

The synergistic action between imidazolium based ionic liquid (IL) [bmim][OcOSO3] and Co(II)/N‐hydroxyphthalimide (NHPI) systems in the catalytic aerobic oxidation of ethylbenzene under solvent‐free conditions have been here demonstrated by reaching a 35 % conversion with 83 % of selectivity in acetophenone at 80 °C. This highly performing catalytic system have been selected after screening several different IL and Co(II) salt combinations, and making sure that the complete solubilization of the polar NHPI in the lipophilic medium, without thus requiring any chemical modification of the organic catalyst, could be attained. This solubilizing effect can be ascribed to a direct interaction between [bmim][OcOSO3] IL and NHPI as revealed by a detailed NMR investigation which also allowed to exclude the formation of higher IL aggregates in the form of micelles or vesicles.

Radical reduction of alkyl halides and aerobic oxidation of alkyl aromatics are reported using water-soluble container compounds (1 and 2). The reductions involve α,ω-dihalides (4–8 and 10) with radical initiators in cavitand hosts with varied binding affinities. Product distributions lead to general guidelines for the use of dynamic supramolecular systems with fast reactions. The binding of guest substrates in the hosts must show high affinities (K a > 103 M–1) to ensure that the reactions take place under confinement in the containers.

A new class of lipophilic N-hydroxyphthalimide (NHPI) catalysts designed for the aerobic oxidation of cumene in solvent-free conditions was synthesized and tested. The specific strategy proposed for the introduction of lipophilic tails on the NHPI moiety leads to lipophilic catalysts that-while completely preserving the activity of the precursor-allow the catalytic oxidation to be conducted in neat cumene, for the first time. The corresponding cumyl hydroperoxide is obtained in good yields (28-52 %) and with high selectivity (95-97 %), under mild conditions. Importantly, the presence of a polar solvent is no longer required to guarantee complete solubilization of the catalyst. On the other hand, the oxidation conducted in neat cumene reveals the unexpected necessity of using small amounts of acetonitrile to fully promote the hydrogen atom transfer process and prevent the catalyst from detrimental hydrogen-bond (HB) driven aggregation.

The cavitand induced “yo-yo” motion was applied to mono-epoxidation reaction of α,ω-dienes using N-bromosuccinamide and K2CO3 in D2O.

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