Metal/Peroxide‐Free [5 + 1] Cyclization of 2‐Vinylanilines with tert‐Butyl Nitrite to Access Diverse Cinnolines

Abstract An efficient metal/peroxide‐free [5 + 1] cyclization of 2‐vinylanilines with TBN was realized to access various cinnolines with high yields. In addition, benzo[ e ]pyrrolo[2,1‐c][1,2,4]triazines could also be obtained by using 2‐(1 H ‐pyrrol‐1‐yl)anilines as the raw materials. This cascade system selected common/low‐cost tert ‐butyl nitrite as the N1 source, which performed broad substrate scopes/simple operation/mild conditions/available scaled up to 1 mmol.