Facile and Efficient Synthesis of Fluorescence‐Labeled RAFT Agents and Their Application in the Preparation of α‐,ω‐ and α,ω‐End‐Fluorescence‐Labeled Polymers

The novel fluorescence‐labeled RAFT agents 2‐(4‐benzyl)benzoxazole benzodithioate (BBB) and 2‐(4‐benzyl)benzoxazole 9H‐carbazole‐9‐carbodithioate (BBCC) were synthesized via a nucleophilic substitution reaction between commercially available 2‐(4‐(chloromethyl)phenyl)benzoxazole (CMPB) and excessive carbodithioate or dithiocarbamate salts. BBB bearing benzoxazole at R‐group and BBCC carrying benzoxazole and carbazole at R‐ and Z‐group can be applied to directly obtain α‐ and α,ω‐end‐fluorescence‐labeled polymers, respectively. Considering the mild reaction conditions and readily available dyes, the reactions between CMPB and dithiocarbamate or carbodithioate salts should be a very simple and promising approach to synthesize fluorescent RAFT agents and polymers.