Nanocellulose as Reaction Medium for FeCl3‐Mediated Mechanochemical Deaminative Fluorination of (Hetero)aromatic Amines

Abstract The development of an efficient alternative to the widely employed Balz‐Schiemann deaminative fluorination method (i. e. without using aryl diazonium tetrafluoroborate salt) is a challenging task. Herein, we report a convenient one‐pot method for the FeCl 3 ‐nanocellullose mediated mechanochemical synthesis of fluoroarenes through the selective substitution of an aromatic amino group by fluorine group using pyrylium tetrafluoroborate (Pyry‐BF 4 ) and sodium fluoride (NaF) via in situ formation of pyridinium salt intermediate. The scope of the present protocol includes synthesis of thirty‐four organofluorine compounds with excellent yields via a selective substitution (S N Ar) of an amino group by fluorine. The presented concise methodology opens a pathway to access new chemical spaces for the late‐stage functionalization in pharmaceutical industries.