2-Hydroxy-1,4-naphthoquinone, 2-hydroxy-3-methyl-1,4-naphthoquinone, 3-hydroxy-2,3-diphenylindan-1-one, 3,4-diphenyl-1H-isochromen-1-one and benzoic acid are prepared in good yield by radical coupling reaction of the electrogenerated radical anion of 1,4-naphthoquinone, 2-methyl-1,4-naphthoquinone, 2,3-diphenyl-1-H-inden-1-one or phenylacetylene respectively, with simultaneously electrogenerated superoxide anion. (C) 2016 Elsevier B.V. All rights reserved.