Science of Synthesis

Lin, S.; Yan, L.; Liu, P., Science of Synthesis, (2007) 20, 104.

Ruthenium(IV) oxide was introduced as an oxidant for organic compounds in 1953.[‌44‌] Since then, its utility for a variety of transformations has been widely recognized; however, the expense of ruthenium provided an incentive for the development of catalytic procedures, the most popular of which involves the use of periodate or hypochlorite as the stoichiometric oxidant.[‌45‌] Indeed, the optimization of these conditions in the early 1980s[‌46‌] led to the widespread use of ruthenium(III) chloride/sodium periodate or ruthenium(IV) oxide/sodium periodate in acetonitrile/carbon tetrachloride/water for the oxidation of aldehydes. A catalytic cycle takes place during the oxidation, in which the lower-valent ruthenium species [Ru(III) or Ru(IV)] is converted into a ruthenium(VIII) catalyst that acts as the actual oxidant. The inclusion of acetonitrile in the solvent system is important as without it the formation of insoluble lower valent ruthenium carboxylate complexes may slow down or even halt the reaction. When present, however, the oxidation-resistant ligand acetonitrile allows the formation of soluble ruthenium–acetonitrile complexes that return the catalyst to the catalytic cycle.[‌36‌] ‌Scheme 14‌ illustrates the oxidation of some complex aldehydes ‌33‌, ‌35‌, and ‌37‌ to the corresponding carboxylic acids ‌34‌, ‌36‌, and ‌38‌ using these conditions.[‌47‌–‌49‌]

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References

Meeeeee Meeeeeeeeee

• 8.Meeeee-Meee, (8888) 8/8e, 888.
• 8.Meeeee-Meee, (8888) M 8-8, 888.