Effect of the number of methylene groups per molecule on the reactivity of both amino and carboxyl groups in hydrogen-isotope exchange reaction

In order to reveal to what extent the number of methylene groups per molecule can have an effect on the reactivity of a material having two different kinds of functional groups, the hydrogen-isotope exchange reaction (T-for-H exchange reaction) between HTO vapor and one of aliphatic compounds having both COOH and NH, groups has been observed in the gas-solid system at a range of 50 similar to 80 degrees C. The rate constants for both COOH and NH2 groups in each material were obtained by applying the A ''-McKay plot method to the data observed. Comparing the rate constants has lead to the following three conclusions. (1) The reactivity of the two groups increases with a rise in temperature. (2) The greater the number of methylene groups is, the smaller the reactivity is of the material (i.e., the smaller the reactivity is of both the COOH and NH2 groups in the material). (3) The reactivity of certain aliphatic materials having two different kinds of functional groups can only be analyzed with the A ''-McKay plot method as well as certain aromatic materials having two different kinds of functional groups.