Aldehydes with argentic oxide

A somewhat similar oxidation takes place when an aldehyde is treated with sodium cyanide and manganese dioxide or argentic oxide [382], The reaction is assumed to proceed through a cyanohydrin, which is oxidized to an a-keto nitrile. The a-keto nitrile in turn is converted into an acid (by argentic oxide in methanol) or an ester (by manganese dioxide in methanol). The method is especially suited for a, -unsaturated aldehydes [382] (equation 354). 

The use of silver (II) salts, particularly argentic picolinate, as reagents for hydroxyl oxidation has also been disclosed recently. The reaction may be run in acid, neutral or basic media in aqueous or polar organic solvents at room or slightly elevated temperatures. Primary alcohols may be oxidized to aldehydes or acids depending on the conditions used. Amines and trivalent phosphorous compounds are more sensitive to oxidation with this reagent than are hydroxyl groups. 

The characteristic color reaction of nicotinic acid with cyanogen bromide and /3-naphthylamine has been studied. The product is believed to be X-201. Argentic picolinate is a powerful oxidizing agent Thus, toluene is oxidized to benzyl alcohol, benzaldehyde, and benzoic acid in a stepwise, controllable manner. Primary alcohols were converted to aldehydes, secondary alcohols to ketones. Amines were oxidized to aldehydes or ketones in dimethylsulfoxide. 

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