An Improved Synthesis of Multi-Substituted Pyrazines under Catalyst- and Solvent-Free Conditions

A one-pot pseudo four-component reaction between a variety of 2-hydroxy-1,2-diarylethanone derivatives and ammonium acetate or amines has been developed to synthesize substituted pyrazines under catalyst-free and solvent-free conditions. This procedure provides a synthetic method to access pyrazine derivatives in excellent yields under green conditions.