Preparation of α , ω ‐heterobifunctionalized poly( N ‐vinylpyrrolidone) via a bis‐clickable RAFT reagent

A novel trithiocarbonate reversible addition−fragmentation chain transfer (RAFT) reagent, 3-azidopropyl (4-[fluorosulfonyl]benzyl)trithiocarbonate (Az-FSBCT), which has both clickable azidopropyl and sulfonyl fluoride moieties, was designed and synthesized. Using the RAFT agent Az-FSBCT and triethylboron as an initiator, well-defined poly(N-vinylpyrrolidone) (PVP), in which the azide and sulfonyl fluoride groups are at the α and ω positions of the polymer chains, were prepared without prior deoxygenation at room temperature. Moreover, the possibilities for the construction of new functionalized polymers were also demonstrated by a “click” copper(I)-catalyzed alkyne-azide cycloaddition (CuAAC) and sulfur(VI)-fluoride exchange (SuFEx) postreaction using these terminal functional PVPs.