Nucleophilic addition to C,C-double bonds. VI. Intramolecular addition of primary amines to C,C-double bonds induced by steric compression

The tricyclic olefinic primary amine 1 readily cyclizes to the tetracyclic secondary amine 2 at approximately 200° in protic as well as aprotic solvents although the C, C-double bond is not activated by electron-attracting groups. This unusual intramolecular addition is the consequence of the close proximity of the nucleophile and the double bond. For the synthesis of the sterically highly hindered amine 1 , the tricyclic oxime 4 was reduced with TiCl₃ to the remarkably stable imine 5 and the latter treated with AlH₃. On the other hand, reaction of 4 with AlH₃ yielded the pentacyclic aziridine 6 .