Kinetics of formation, dissociation, and redox reactions of the benzyl radical‐Cu(II) ion complex in a 10% acetonitrile‐90% water mixture

The rate constant of formation, dissociation, and redox reaction of the benzyl radical‐copper(II) ion complex have been determined at temperatures from 274 K to 333 K by laser flash photolysis of 1,3‐diphenyl‐2‐propanone (DBK) in a 10% acetonitrile‐90% water mixture containing copper(II)perchlorate. Rate constants were calculated from time resolved absorbances of both benzyl radicals (Bz) at 315 nm and benzyl‐copper complexes (BzCu²⁺) at 375 nm. Values of the rate constants of the formation of BzCu²⁺ complex were fitted to the equation (Formula Presented.) and the rate constant of the reverse reaction of BzCu²⁺ complex to the equation (Formula Presented.) The rate constant of the redox reaction of BzCu²⁺ complex to benzyl alcohol and copper(I) ion can be described by the equation (Formula Presented.) The first order rate constant of dissociation of phenylacetyl radical formed initially in the flash photolysis of DBK is given by the equation (Formula Presented.)