Radiation-induced reactions of benzoyl chloride and acrylates in solution.A pulse radiolysis study

Using electron pulse radiolysis with optical detection, the radiation-induc ed reactions of benzoyl chloride and acrylates were studied in tetrahydrofu ran and acetonitrile solution at room temperature. In both solvents electro n transfer leads to the formation of transient radical anions of acrylates (k approximate to 2-3 x 10(10) dm(3) mol(-1) s(-1)) and of benzoyl chloride (k approximate to 3 x 10(10) dm(3) mol(-1) s(-1)). The latter dissociates into chloride ion and the benzoyl radical (k = 3 x 10(6) s(-1)), whereas th e acrylate anion transforms by protonation into a ketyl-type radical. In mi xed solutions a fast electron transfer from acrylate anions to benzoyl chlo ride is found (k approximate to 1 x 10(10) dm(3) mol(-1) s(-1)). The benzoy l chloride anion reacts with the monomer (k = 2.8 x 10(9) dm(3) mol(-1) s(- 1)) with simultaneous release of Cl-, forming species which may initiate po lymerization. In the presence of oxygen the formation of benzoylperoxy radi cals (k = 1.6 x 10(9) dm(3) mol(-1) s(-1)), showing a strong absorption ban d in the near-UV (lambda(max) = 400 nm), is observed.