The reaction of an aminocoumarincarboxylic acid chloride (Coumarin 343) with 1-phenethyl hydroperoxide results in light emission that is easily detected with the unaided eye. This reaction proceeds through a secondary perester intermediate. Intramolecular electron exchange, modeled after the analogow procw in the bioluminescence of the firefly, is proposed as the mechanism for light generation. Attempts to carry out this reaction under ...