テオフィリンとエチレンジアミン類似化合物との固体複合体

抄録

Solid complex formation of theophylline with ethylenediamine analogues, namely, 1, 4-butanediamine, 1, 5-pentanediamine, 1, 6-hexanediamine, 1, 7-heptanediamine, and 1, 8-octanediamine was attempted from an aqueous and an absolute ethyl alcohol solution. Theophylline forms solid complexes with diamines except 1, 5-pentanediamine and 1, 7-heptanediamine from absolute ethyl alcohol solution, and if forms solid complexes with every diamine from an aqueous solution, in molar ratios of 2 : 1. The solid complexes of 1, 5-pentanediamine and 1, 7-heptanediamine contain two and one molecule of crystal water, respectively. Since these crystal waters combine to the solid complexes weaker than those of aminophylline and the complex of 1, 3-propanediamine, it can be presumed that the solid complexes of 1, 5-pentanediamine and 1, 7-heptanediamine are not formed from absolute ethyl alcohol solution. To study the thermal decomposition of the complexes, differential thermogravimetric analysis was carried out in air, at a temperature elevation rate of 2.5°/min. It showed that the solid complexes having no crystal water, eliminate each diamine accompanied with each endothermic peak in certain temperature ranges and that the solid complexes having crystal water, first lose each crystal water to anhydrous solid complexes in certain temperature ranges and then eliminate each diamine. By applying the equation proposed by Freeman and Carrol, the activation energies of the eliminations of diamines of the complexes of 1, 4-butanediamine, 1, 5-pentanediamine, 1, 6-hexanediamine and 1, 8-octanediamine were calculated as 95.8, 59.0, 66.1, and 71.8 kJ/mol, respectively, and orders of reaction of these, calculated to zero without exception.