2000 Volume 49 Issue 6 Pages 285-291
In order to reveal the reactivity of each functional group in the compound having three functional groups per molecule, the hydrogen-isotope exchange reaction (T-for-H exchange reaction) between disubstituted phenol and tritiated water vapor (HTO vapor) was dynamically observed at 50, 60, and 70°C in a gas-solid system. The data obtained in the observation increased with increasing observed time, and it was found that T-for-H exchange reaction occurred. Applying the A″-McKay plot method to the data obtained, the reaction was dynamically analyzed. The rate constant (k) of each functional group for the reaction was consequently obtained. These k's obtained and k's obtained previously were compared with each other. When the additive property of the Hammett rule was applied to the k's obtained in this work, the new substituent constants were obtained. The new constants were fitted on the Hammett plot obtained previously. From the above-mentioned, the following five matters have been clarified. (1) The reactivity of different functional groups can be compared with each other by applying the method used in this work. (2) The reactivity of the functional groups can be dynamically analyzed, and the A″-McKay plot method is useful to analyze the reactivity. (3) The additive property of the Hammett rule, which is generally used in the field of organic chemistry in order to compare the chemical reactivity of organic materials, is applicable to quantitative comparison of the reactivity of the functional groups. (4) The reactivity of the functional groups can be simultaneously (and unchangeably) analyzed by using the T-for-H exchange reaction. (5) The method used in this work is useful to analyze the reactivity of a material having many kinds of functional groups.
