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The oxidation of alcohols to aldehydes, ketones, and carboxylic acids is reported using 2,2,6,6‐tetramethylpiperidine‐4‐acetamido‐hydroxyammonium tetrafluoroborate as a catalyst in conjunction with sodium hypochlorite pentahydrate as a terminal oxidant. The reaction is generally complete within 30–120 min using an acetonitrile/water mix as the solvent, and no additives are required. Product yields are good to excellent and of particular note is that the methodology can be used to access aryl α‐trifluoromethyl ketones.

A methodology for the direct introduction of the trifluoromethyl group on to indole scaffolds is presented. The procedure involves the use of sodium trifluoromethylsulfinate (Langlois reagent) as the source of the trifluoromethyl radical, and is performed photochemically with 2-tert-butylanthraquinone as a photocatalyst. The reaction has also been probed computationally. Reaction kinetics and molecular orbital analyses from our quantum chemical computations successfully predict and rationalize the formation of the experimentally observed product and, in the case of 1-methylbenzimidazole, even reproduce the same qualitative trends in regioisomer preference. Lefebvre later reported a hydrotrifluoromethylation method which

A systematic study of the oxidation of a range of terminal diols is reported, employing the oxoammonium salt 4-acetamido-2,2,6,6-tetramethylpiperidine-1-oxoammonium tetrafluoroborate (4-NHAc-TEMPO BF) as the oxidant. For substrates bearing a hydrocarbon chain of seven carbon atoms or more, the sole product is the dialdehyde. A series of post-oxidation reactions have been performed showing that the product mixture resulting from the oxidation step can be taken on directly to a subsequent transformation. For diols containing four to six carbon atoms, the lactone product is the major product upon oxidation. In the case of 1,2-ethanediol and 1,3-propanediol, when using a 1 : 0.5 stoichiometric ratio of substrate to oxidant, the corresponding monoaldehyde is formed which reacts rapidly with further diol to yield the acetal product. This is of particular synthetic value given both the difficulty of their preparation using other approaches and also their potential application in further reaction chemistry.

The effect of varying the counterion in the oxoammonium salt mediated oxidation of alcohols has been probed. Computational and experimental results suggest that the counterion is non-innocent in oxoammonium salt mediated [a]

A simple, solvent-free methodology is reported for the direct conversion of esters to amides using lithium hydroxide as a catalyst.

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