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Z. Naturforsch. 2014,
69b, 641 – 649
doi:10.5560/ZNB.2014-4002
Novel Dihydropyrazines and their Double ortho-Annulation to Hexaazapentacenes
1 Institut für Organische Chemie und Makromolekulare Chemie, Friedrich-Schiller-Universität Jena, Humboldtstr. 10, D-07743 Jena, Germany
2 Present address: Biomolecular Photonics Group, Jena University Hospital, Nonnenplan 4, D-07743 Jena, Germany
3 Klinikum Bad Berka, Department of Molecular Radiotherapy / Center for Molecular Imaging, D-99437 Bad Berka, Germany
4 Institut für Anorganische und Analytische Chemie, Friedrich-Schiller-Universität Jena, Lessingstr. 8, D-07743 Jena, Germany
Reprint requests to Prof. Dr. R. Beckert. E-mail:
Rainer.Beckert@uni-jena.de
Received January 8, 2014 / published online May 7, 2014
Dedicated to Professor Peter Metz, Dresden, on the occasion of his 60th birthday
The cycloacylation of oxalic amidines 7 with bis-imidoylchlorides 6 furnished the dihydropyrazine derivatives 8. Due to their vicinal amino-imino substructures, they provide good preconditions for a double intramolecular ring closure reaction. An alternative synthesis for hexaaza-pentacenes 1 was developed using potassium carbonate as the base and lead tetraacetate as the oxidizing agent.
Key words: Hexaazapentacenes, Dihydropyrazines, ortho-Annulation, Amidines, Fluorophores