Conformation dibenzo diazocines

Dibenzo[b,/][l,5]diazocine, tetrahydro-conformation, 7, 704 Dibenzo[b,/][l,4]diazocinediones synthesis, 7, 675 Dibenzodioxin, 2,7-dichloro-toxicity, 3, 992 Dibenzodioxin, hexachloro-toxicity, 3, 992 Dibenzodioxin, octachloro-toxicity, 3, 992... 

The tetrahydrodibenzo[6,/][l,4]diazocines (458) and the tetrahydrodibenzo[6,/]-[l,5]diazocines (459), which have two nitrogens in the heterocyclic ring, as well as their sulfur analogs (460) and (461) show conformational properties similar to those of the monoaza compound (456). Typical data are included in Table 3. The assignments of conformations and transition states for these dibenzo derivatives are supported by force-field calculations and by detailed dynamic NMR measurements <73JCS(Pl)205>. 

Proton and C nuclear magnetic resonance (NMR) analyses of a variety of 1,4-diazocine derivative have been reported, in the context of both detailed conformational analysis and assessment of potential aromaticity as well as routine structural characterization. Fully unsaturated 1,4-diazocines appear to be represented only as their dibenzo[A/] and dibenzo[e, ] derivatives. A variety of NMR analyses have confirmed or demonstrated the nonplanarity of the diazocine ring in (12 X = NMe,... 

Little reaction chemistry has been reported for the comparativeiy rare fuily-unsaturated 1,5-diazocines, although valence isomerization and a handful of other reactions, particularly of the dibenzo[i/][l,5]diazocines, have been reported, as summarized in CHEC-I (Section 5.19.4.5) and in reviews <87H(26)2477, 89AHC(46)1>. These derivatives are discussed here rather than in a separate section devoted to fully-conjugated compounds, as their decidedly nonplanar conformations clearly obviate any possibility of delocalized bonding. 

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