One‐Step and Mild Synthesis of 3‐(1,3,4‐Oxadiazol‐2‐Yl)isoindolin‐1‐Ones Through Ugi Four‐Component Domino Dicyclization

A novel and efficient Ugi four‐component domino dicyclization strategy has been developed for one‐step constructing diverse 3‐(1,3,4‐oxadiazol‐2‐yl)isoindolin‐1‐ones with good yields, without the need for additional additives. This domino dicyclization process underwent three consecutive reactions including Ugi, aza‐Wittig and N‐acylation by utilizing (N‐isocyanimine)triphenylphosphorane, methyl 2‐formylbenzoate, primary amines, and carboxylic acids. The initial biological activity testing revealed that compound 5 i exhibited good antifungal activity against certain fungi and demonstrated versatile applications in the fields of pesticide chemistry.