Boron Trifluoride‐Catalyzed Synthesis of 3‐Alkylidene‐3H‐indole N‐Oxides via Tandem Reaction of Propargylic Alcohols and Nitrosobenzenes

Abstract An atom‐economical synthesis of 3‐alkylidene‐3 H ‐indole N ‐oxides has been developed via a tandem reaction of propargylic alcohols and nitrosobenzenes in the presence of boron trifluoride etherate (BF 3 ⋅Et 2 O) as catalyst. This method offers great potential for the synthesis of biologically important 3‐alkylidene‐3 H ‐indole N ‐oxides and related derivatives. magnified image