2-Azidoethane-1-sulfonylfluoride (ASF): A Versatile Bis-clickable Reagent for SuFEx and CuAAC Click Reactions

A new reagent, 2-azidoethane-1-sulfonylfluoride (ASF), was synthesized from 2-chloroethane-1-sulfonyl fluoride in 50g-scale with 87 % yield. This novel reagent possesses two selectively clickable functionalities to be used for both CuAAC and SuFEx click reactions. The application of this reagent ASF to the construction of a class of novel 1,2,3-triazole derived S(VI)-F analogs was achieved in a quick, efficient and atom-economical manner. Orthogonally clickable construction of a new class of dendrimers was also accomplished.