CONFORMATIONAL-ANALYSIS OF HETEROCYCLIC-ANALOGS OF 5,6,11,12-TETRAHYDRODIBENZO[A,E]CYCLOOCTENE - AHYDROBISBENZIMIDAZO[1,2-A2-1',2'-E][1,5]DIAZOCINE AND 4-TETRAHYDROBISPYRIDO[1,2-A-1',2'-E]DIAZODINEDIIUM DIBROMIDE

The H-1 and C-13 NMR spectra of the title compounds have been recorded . While the spectrum of trahydrobisbenzimidazo[1,2-a:1'.2'-e[1,5]diazo cine 3 does not show any dependence with the temperature in the studie d range (-65 to +75 degrees C), that of 6,7,13,14-tetrahydrobispyrido[ 1,2-a:1',2'-e] diazocinediium dibromide 4 shows a clear variation, nar row lines appearing only at +85 degrees C. The differences in the dyna mic behaviour of these compounds has been analyzed using different sem i-empirical calculations (MNDO, AM1, PM3) of the ground and transition states. For comparison purposes, two other compounds belonging to the 6,8,6 series of ring derivatives have also been calculated, 5,6,11,12 -tetrahydrodibenzo[a,e]cyclooctene 1 and 5,5,12.13 ispyrazolo[1,2-a:1' ,2'-e][1,2,5,6]tetrazocinediium cation 2. (C) 1998 Elsevier Science Lt d. All rights reserved.