Synthesis of Aryl-Substituted 1,4-Dihydroquinolines by [4+2] Cycloaddition of Benzyne with 1-Azadienes

The synthesis of aryl-substituted 1,4-dihydroquinolines can be achieved using a [4+2] cycloaddition between benzyne and various aryl-substituted 1-azadienes. The conditions are tolerated by N-aryl-, alkyl-, tosyl-, and tert-butoxycarbonyl-protected 1-azadienes. A short synthesis of the fungal metabolite 3-O-methylviridicatin is reported.