ABSTRACT The pulse radiolysis method has been used to determine the reactivity of various alcohols towards chlorine atoms in carbon tetrachloride at 18°C using the competition kinetic method taking the absorption of the complex formed by the reaction of dimethyl sulfoxide and chlorine atoms as a reference system. The rate constants of normal alcohols increase lineary with increasing number of carbon atoms up to 7 reaching a plateau value, ca. 8.0 x 109 mol-1 dm3 s-1. Among isomers more branched alcohols exhibit lower reactivity than normal alcohols. The reaction rate constants can be explained in terms of the summation of partial reactivities of hydrogens as assigned to primary, secondary and tertiary bound to α-, β-, γ-, δ-, and ε-carbon atoms in the alcohol molecules. The reaction rate constants of deuterated alcohols are also measured. The deuterium isotope effects indicate that the rate determining step is the hydrogen abstraction process by the chlorine atom. The preference for the alkyl hydrogen abstraction is also demonstrated.
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