An efficient and convenient protocol for the synthesis of quinoxalines and dihydropyrazines via cyclization–oxidation processes using HClO4·SiO2 as a heterogeneous recyclable catalyst

• DOI: 10.1016/j.tetlet.2007.06.036
• Publication Date: 2007-06-11T13:39:51Z
• Authors: Biswanath Das; Katta Venkateswarlu; Kanaparthy Suneel; Anjoy Majhi
• Keywords: 01 natural sciences; 12. Responsible consumption; 0104 chemical sciences

A convenient and straightforward method has been developed for the synthesis of quinoxalines and dihydropyrazines (DHPs) using α-bromo ketones and 1,2-diamines in the presence of silica supported perchloric acid (HClO4·SiO2) at room temperature. The quinoxalines and DHPs were presumably formed via cyclization–oxidation. The catalyst works under heterogeneous conditions and can be recycled.