Certain organic reactants which are free from aliphatic unsaturation and which are capable of yielding free radicals upon treatment with peroxides are oxidized, in the liquid phase in an aqueous medium, with certain peroxy compounds to form freeradical intermediates which are then allowed to react further with themselves or with other components of the reaction medium to form useful end products. Preferred features include the slow addition of the peroxy compound to the reaction zone and the use of certain metalic ions to improve yields. The process may be used for the reaction of HCN and carboxylic acids to produce nitriles; the conversion of tertiary alkanols to ketones; and the production of cyanogen from hydrogen cyanide.