Water-promoted defluorinative synthesis of fluoroalkylated 1,5-diazapentadienes by using (NH4)2CO3 as an NH2 and NH source

Abstract

A H₂O-promoted and (NH₄)₂CO₃-enabled deiodoamination and defluoroiminization reaction of fluoroalkyl alkenes has been developed under transition-metal-free conditions. Structurally important fluoroalkylated 1,5-diazapentadienes were obtained in excellent Z-selectivity with good functional group tolerance. The versatility of the method was illustrated in the synthesis of valuable organofluorides from the obtained products. Compared to traditional synthetic methods, several apparent limitations, including distillation for purification, multistep manipulation, harsh reaction conditions, moisture exclusion, and the use of toxic/sensitive reagents, could be avoided. The key to the success of the reaction is the use of (NH₄)₂CO₃ as a commercially available, inexpensive, low-toxic, and efficient NH₂/NH source and water as a C(sp³)–F bond cleavage promoter. Moreover, the distinctive fluorine effects of perfluoroalkyl substituents on substrates are also vital for enhancing the reaction efficiency.