| Abstract: | Five new ionenes were synthesized from tertiary diamines and dihalides. For comparison, four bromo-ionenes were also prepared. Due to a lower C-Br bond energy the bromo-ionenes can be prepared from alkylene dibromides and tertiary diamines, whereas in case of chloroionenes the presence of electronegative atoms or groups of atoms in the dichlorides proved to be the condition to ensure reaction under moderate conditions. The highest initial reaction rates and lowest energies of activation (27,2–35,5 kJ/mol) were observed in runs with 1,3-dichloro-2-propanon ( 1 ). Similarly, bis(2-chloroethyl) ether ( 2a ) proved to be a convenient dihalide for the formation of chloro-ionenes, displaying reactivities comparable with those of 1,6-dibromohexane. All reaction orders referring to the preparation of bromo-ionenes investigated, were found to be about 2, whereas the formation of chloro-ionenes is first order. In case of bromoionenes the energies of activation were higher (66,7–79,8 kJ/mol) than in the case of chloroiones (27,2–51,8 kJ/mol). The structure of tertiary diamines plays an important role as far as their basicity is concerned, influenced by resonance conjugation, which is the case with Michler's ketone ( 5 ) as well as with tetramethylurea ( 6 ). The ionenes resulting from the dihalides and tertiary amines proved to be oligomers. |
