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Since their inception in the mid 90s, living radical polymerizations (LRP) have undergone a remarkable development and have become one of the most useful and dynamic synthetic methods in modern polymer chemistry.(1) The ability of LRP to control molecular weight (Mn) and polydispersity (Mw/Mn) while requiring considerably more user-friendly reaction conditions vs. water sensitive ionic and coordination polymerizations has greatly benefited the polymer synthesis toolbox and has enabled its wide use in the synthesis of complex macromolecular structures. Accordingly, such LRP applications have motivated extensive efforts in the development of novel catalytic systems. It is currently accepted that the polymerization livingness is afforded by the reversible termination of the growing chains with persistent radicals (2) or degenerative transfer agents and that mechanistically,(3) LRP occurs by atom transfer (ATRP), dissociation-combination (DC) or degenerative transfer (DT) processes. Catalyst-wise, organic derivatives such as nitroxide (4) and iodine (5) or sulfur-based transfer agents (6) mediate LRP via DC and respectively DT, while organometallic complexes (7) of Co,(8) Te,(9a) Sb,(9b) Bi,(9c) Mo (10a) and Cr (10b) may favor both DC and DT pathways. Finally, late transition metal halide persistent radicals (2)(Cu, Ni, Fe, Ru, etc)(1, 3, 11) have proven very successful in ATRP.

However, current LRP systems are still somewhat limited by the restrictive choice of only activated halide or thermal initiators, which may restrict chain end functionality, and by the range of monomers polymerizable by a given method.(1) Thus, a broader initiator and …