Metal‐free Cascade Radical Cyclization of N‐Methylacrylyl‐2‐phenylbenzimidazole: Construction of Aryldifluoromethylated Benzimidazole[2,1‐a]iso‐Quinoline‐6(5H)‐ketone

Abstract A facile and effective metal‐free decarboxylative cyclization of N ‐methacryloyl‐2‐phenylbenzimidazole with arylthio (oxy) difluoroacetic acids or α , α ‐aryldifluoroacetic acids was proposed to prepare a series of aryldifluoromethylated benzimidazole[2,1‐ a ] iso ‐quinoline‐6(5 H )‐one derivatives in medium to good yields with good functional group tolerance, readily available raw materials and simple operation. In addition, experimental studies showed that the CF 2 group of arylthiodifluoroacetic acids plays a crucial role in this conversion.