Rate constants for reactions of NO₃^• radicals with organic compounds in water and acetonitrile

Rate constants have been measured for the reactions of the nitrate radical, NO₃^•, with a number of alkanes, alkenes, and arenes in acetonitrile (ACN). The rate constants measured in ACN were greater than the rate constants reported for the same reactions in the gas phase. For several alcohols, rate constants were measured in ACN and in a 60% acetic acid/water solvent. The rate constants in ACN solutions were significantly greater than the values reported previously for aqueous solutions, and those measured in 60% acetic acid were slightly greater than those measured in water. These trends in rate constants are different from those reported for the SO₄^•- radicals, and the differences are discussed in terms of the effect of the solvent on the radicals and on the transition states of their reactions.