Abstract |
Rate constants for the reactions of a variety of naturally occurring nucleophiles with 1-bromohexane and, to a lesser extent, three other haloalkanes were studied in order to assess their importance relative to hydrolysis in determining the environmental fate of haloalkanes. HS(-) is generally the most important nucleophile because it is moderately reactive and, among the reactive sulfur nucleophiles, is usually present in the highest concentration. When elemental sulfur is present, polysulfides will be more important for the consumption of 1-bromohexane than HS(-) at pH above approximately 7 because they are 60 times more reactive and their equilibrium concentrations increase with increasing pH. A nucleophilicity scale valid in pure water was established for environmental nucleophiles, using 1-bromohexane as a reference reactant. (Copyright (c) 1988 SETAC.) |