Oxidative amination and hydroxylation of 1,3,7-triazapyrenes in aqueous medium
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We have already reported the unusual capacity of 1,3,7-triazapyrenes 1a and 1b  and 7-alkyl-1,3,7-triazapyrenium salts [2, 3, 4, 5] to react readily in aqueous solution with O-nucleophilic reagents to give mono- and disubstitution products. This is the result clearly not only of the π-electron deficiency of these compounds but also the specific peri-fusion structure of this heterocyclic system.
The oxidative amination of the most electrophilic heterocycles such as naphthyridines  or 1,2,4-tria-zine  is carried out by action of a solution of KMnO4 in liquid ammonia. We have discovered, however, that 1,3,7-triazapyrenes 1a and 1b may be aminated in a solution of ammonia in aqueous dioxane in the presence of K3[Fe(CN)6]. The reaction proceeds at 50-55 °C to give 6-amino-1,3,7-triazapyrene (2a) in 95% yield and 6-amino-2-methyl-1,3,7-triazapyrene (2b) in 89% yield.
Keywords1,3,7-triazapyrenes nucleophilic replacement of hydrogen oxidative amination oxidative hydroxylation
- 1.O. P. Demidov, I. V. Borovlev, S. V. Pisarenko, O. A. Nemykina, and N. A. Saigakova, Khim. Geterotsikl. Soedin., 791 (2010). [Chem. Heterocycl. Comp., 46, 636 (2010)].Google Scholar
- 2.O. P. Demidov, I. V. Borovlev, S. V. Pisarenko, and O. A. Nemykina, Khim. Geterotsikl. Soedin., 780 (2009). [Chem. Heterocycl. Chem., 45, 619 (2009)].Google Scholar
- 3.O. P. Demidov, I. V. Borovlev, S. V. Pisarenko, and O. A. Nemykina, Zh. Obshch. Khim., 80, 165 (2010).Google Scholar
- 4.I. V. Borovlev, O. P. Demidov, S. V. Pisarenko, N. V. Demidova, and O. A. Nemykina, Zh. Org. Khim., 45, 1739 (2009).Google Scholar
- 5.I. V. Borovlev, O. P. Demidov, S. V. Pisarenko, and O. A. Nemykina, Khim. Geterotsikl. Soedin., 597 (2010). [Chem. Heterocycl. Comp., 46, 473 (2010)].Google Scholar
- 6.H. S. van der Plas, M. Wozniak, and H. J. W. Haak, Adv. Heterocycl. Chem., 33, 95 (1986).Google Scholar
- 7.A. Rykowski and H. S. van der Plas, Synthesis, 884 (1985).Google Scholar