Carbonyl-Enamine a New Mode for Azepine Ring Closure: Synthesis and Characterization of Pyrazino[2,3-c]azepine, as a New Ring System

Mohamed Attia Waly*

Faculty of Science (Damiatta), Chemistry Department Mansoura University, Egypt.
* Corresponding author: E-mail: mohamedwaly7@yahoo.com

Abstract
Pyrazino[2,3-c]azepine and azepino[3,4-b]quinoxaline represent new ring systems and were prepared by fusing either of pyrazine ring onto azepine derivative or vice versa. Intramolecular 1,7-carbonyl-enamine cyclization was studied as a new mode for azepine ring closure. Various examples and reaction conditions were studied for this ring closure.

Keywords: Synthesis, Condensation reaction, α-Bromoketone, Carbonyl-Enamine, Mode of ring closure, pyrazine,
quinoxaline, pyrazinoazepine, azepinoquinoxaline.