TfOH-mediated [2+2+2] cycloadditions of ynamides with two discrete nitriles: synthesis of 4-aminopyrimidine derivatives

In this study, a concise and atom-economical TfOH-mediated [2 + 2 + 2] cycloaddition of ynamides with two discrete nitriles is developed to synthesize multi-substituted 4-aminopyrimidine. A variety of functional groups and sterically and electronically diverse reaction partners are tolerated. The products were obtained in good to excellent yields.