Photoinduced reactions of two toxaphene compounds in aqueous medium and adsorbed on silica gel

Two pure chlorinated bornanes isolated from technical toxaphene^R (1 and 2) were irradiated at different wavelength in neutral aqueous medium, and in a near-monomolecular layer adsorbed on a silica gel surface. Both compounds react to give products which are formed by reductive dechlorination (1a-b and 2a-b), dehydrochlorination (1e and 2e), oxydation (1c, 2c, 1f and 2f) and a combination of these reactions (1d and 2d). In heterogeneous phase the formed ketons (1f and 2f) were converted rapidly to bicyclo-[2,1,1]-hexane derivatives (1g and 2g). Photochemical data e.g. quantum yields, triplet energies and reaction rate constants were presented in this report in order to estimate the half-life of the model substances (1 and 2) in water and, adsorbed on surfaces under simulated environmental conditions.