Selenium‐Mediated Cyclization Reaction of 2‐Vinylanilines with/without Isonitriles: Efficient Synthesis of 2‐Aminoquinoline/ 3‐Aryl‐1H‐indole Derivatives

Herein, we report a non‐metal strategy for cyclization reactions of 2‐vinylanilines with/without isonitriles to synthesize 2‐aminoquinoline and 3‐aryl‐1 H ‐indole derivatives. A series of 2‐aminoquinolines were afforded in good to excellent yields in a direct, facile, and efficient approach by Se‐catalyzed isocyanide insertion with 2‐vinylanilines under an air atmosphere. This reaction not only used low toxicity Se as the catalyst, isocyanobenzene substrates were compatible too compared to previous report. Meanwhile, an intramolecular cyclization of 2‐vinylanilines was developed to give 3‐aryl‐1 H ‐indoles in moderate to good yields by using SeO 2 as oxidant.