Abstract
3-Amino-2H-azirines, cyclic three-membered amidines with an estimated strain of about 200 kJ/mole, undergo a variety of reactions. Thereby, each of the azirine bonds can be broken: Thermolysis leads to the rupture of the C(2),C(3)-bond, with strong acids opening of the N(1),C(2)-bond takes place and the reaction with carboxylic acids leads to the cleavage of the N(1),C(3)-double bond. The versatile reactivity of the 3-amino-2H-azirines is demonstrated by some reactions with NH-acidic heterocycles and with heterocumulenes, respectively. In almost all cases new heterocyclic compounds result from these reactions.