Preparations of formyl-1, 4-benzoquinone, 1, 4-benzoquinonylacetaldehyde, 3-(1, 4- benzoquinonyl) propionaldehyde, 2-(1, 4-benzoquinonyl)-2-methylpropionaldehyde, and 2- methyl-2-(1, 4-naphthoquinon-2-yl) propionaldehyde are described. Irradiation of solutions of these quinones in benzene with visible light leads to the isolation of 2, 5- dihydroxybenzoic acid from formyl-1, 4-benzoquinone, and to the formation of 5- ...
