Photoreactions of the decatungstate anion W10O324− with organic substrates in solution studied by EPR and kinetic absorption spectroscopy: an example for the persistent radical effect

EPR and kinetic absorption spectroscopy experiments reveal the simultaneous formation of transient radicals and a persistent reduced tungsten radical species during the photoreaction of W10O324– with organic substrates in solution. It is shown that a special kinetic effect operates which causes the observed selective product formation. Theoretical predictions on the ratio of radical concentrations and on their time developments are confirmed. Moreover, some mechanistic aspects of the reactions are clarified.