The electrochem. behavior of some model org. compds. on boron-doped synthetic diamond thin film electrodes, obtained by HF-CVD on p-Si substrate was investigated. Only reactions involving simple electron transfer like hydroquinone/benzoquinone are active in the potential region of the supporting electrolyte stability, although this system is irreversible on diamond electrodes. For oxidn. reactions with more complex mechanism, diamond electrodes show no electrocatalytic activity in the potential region of the supporting electrolyte stability. These complex oxidn. reactions can take place on diamond electrodes in the potential region of the supporting electrolyte decompn. The reactivity of some alcs. and carboxylic acids is studied by cyclic voltammetry. Isopropanol in 1 M H2SO4 is oxidized on diamond anode at a const. c.d. and the intermediates formed are analyzed by HPLC. Finally, a simplified mechanism for the oxidn. of orgs. by electrogenerated OH radicals on diamond is proposed. [on SciFinder (R)]