Adducts of the 3,4-Diazabicyclo [4.2.0] Octa-2,4.7-Triene System

Abstract

Cyclooctatetraene is known to be in equilibrium with its valence isomer bicyclo{4.2.0} Octatriene, although the equilibrium is dramatically in favour of the monocyclic form¹. This latter valence ismer is extremenly reactive in π⁴π₈ cycloaddition reactions² and readily form stable adducts. Azaanalogues of this carbocyclic system are also of interest in heteroalicyclic chemistry, but few methods for their synthesis have yet appeared. Azocines have received some attention of late^3,5, and the recent work of Paquette's group⁴ is particularly impressive in this respect. Although the parent azocine is extremely unstable it too has recently been described⁵, The 1,2-diazocines, however are even less accessible although Maier and co-workers⁶ have prepared the diazocines (3–5) as outlined in Scheme 1.