ECHET96 Article 103: Prof. Lucio Pellacani
Re: ECHET96 Article 103: Joachim Schantl
Azimines, azo-aziridines, 1,2,3-triazoles. Products obtained from the oxidation of N-aminophthalimide in the presence of azo-alkenes
aSt. Petersburg State University, St. Petersburg, 198904 Russia
bInstitut für Organische Chemie, Universtät
Innsbruck, Innrain 52a, A-6020 Innsbruck, Austria
Introduction
Oxidation of N-aminophthalimide with lead tetraacetate carried
out in the presence of an olefinic substrate gives rise to the formation of
N-aminoaziridine derivatives [1-5]. It is well accepted that
1,1-disubstituted aminonitrenes can be generated by the oxidation of the
corresponding 1,1-disubstituted hydrazines, this reaction has been considered
as an aminonitrene cycloaddition to C=C-bonds [1-3]. More recently, Atkinson et al. [4] as well as others [5, 6] have shown and
discussed that lead tetraacetate oxidation of N-aminophthalimide and
related N-aminoheterocycles involves the N-acetoxyhydrazine
intermediate rather than the N-aminonitrene. Regardless of the actual
type of intermediate, the "oxidative aminoaziridination" is a convenient method
for the synthesis of N-aminoaziridines.
Lead tetraacetate oxidation of N-aminophthalimide in the presence of azo
compounds affords phthalimidoazimines, a new class of 1,3-dipolar species
[2,3,7].
Azo-alkenes (a,b-unsaturated azo compounds) [8] containing both functional
groups aroused our interest to investigate the chemoselectivity of this
reaction. To this goal, N-aminophthalimide was oxidized with lead
tetraacetate in the presence of several azo-alkenes.
- B.V. Ioffe, M.A. Kuznetsov, A.A. Potekhin, "Chemistry of the
Organic Hydrazine Derivatives" Khimiya, Leningrad, 1979, p. 224.
-
R.S. Atkinson in "Azides and Nitrenes. Reactivity and Utility" ed.
E.F.V. Scriven, Academic Press, New York, 1984, p. 247.
-
M.A. Kuznetsov, B.V. Ioffe, Uspekhi Khimii, 1989, 58,
1271; Russ. Chem. Rev., 1989, 58, 732.
-
R.S. Atkinson, B.J. Kelly, J. Chem. Soc., Chem. Commun. 1987,
1362.
-
D.W. Jones, M. Thorton-Pett, J. Chem. Soc., Perkin Trans. 1
1995, 809.
-
R.S. Atkinson, E. Barker, J. Chem. Soc., Chem. Commun., 1995,
819.
-
A.A. Suvorov, M.A. Kuznetsov, Uspekhi Khimii, 1987, 56,
1324; Russ. Chem. Rev. 1987, 56, 756.
-
J.G. Schantl in Houben-Weyl, "Methoden der Organischen Chemie" vol.
E15, Georg Thieme, Stuttgart-New York, 1993, 909.
Scheme 1 Oxidation of 1,1-disubstituted hydrazines in the presence of olefins and azo
compounds: N-aminoaziridines and azimines
Scheme 2 Azo-alkenes; syntheses
Scheme 3 (E)-b-Phenylazo-stilbene, N-aminophthalimide, lead tetraacetate: 2-phenyl-3-phenylazo-1-phthalimidoaziridine
Scheme 4 (E)-1-phenylazo-1-cyclohexene, N-aminophthalimide, lead tetraacetate: syn-2-phenylazo-1-phthalimidoperhydrocyclohexa[b]aziridine
Scheme 5 (E)-1-phenylazo-1-cyclopentene, N-aminophthalimide, lead tetraacetate:
2-phenyl-2,4,5,6-tetrahydrocyclopenta[d][1,2,3]triazole
Scheme 6 (E)-2-phenylazo-propene, N-aminophthalimide, lead tetraacetate: 4-methyl-2-phenyl-1,2,3-triazole and phthalimide and
(2-phenylhydrazonopropylideneamino)phthalimide [via ene-azimine?]
Scheme 7 3,3,5-Trimethyl-3H-pyrazole, N-aminophthalimide, lead tetraacetate: (E)- and
(Z)-3,3,5-trimethyl-3H-pyrazolium-2-(phthalimido)imide and
(Z)-3,3,5-trimethyl-3H-pyrazolium-1-(phthalimido)imide
