Visible-light hypervalent iodide carboxylate photo(trifluoro)methylations and controlled radical polymerization of fluorinated alkenes.

IFAB-ulous trifluoromethylation: (CX3COO)2I(III) h (X=F, H) and (CH3COO)3I(V)(C6H4COO) are introduced as CX3·/CX3I precursors for metal-free, visible-light, radical (trifluoro)(iodo)methylations of alkenes, illustrated by their use as photoinitiators for the controlled radical polymerization of vinylidene fluoride with external (I(CF2)6I) and in situ generated (CF3I) iodine chain transfer agents, and for block copolymer synthesis.

Mild-temperature Mn2(CO)10-photomediated controlled radical polymerization of vinylidene fluoride and synthesis of well-defined poly(vinylidene fluoride) block copolymers.

By contrast to typical high-temperature (100-250 °C) telo-/polymerizations of gaseous fluorinated monomers, carried out in high-pressure metal reactors, the visible light, Mn(2)(CO)(10)-photomediated initiation of vinylidene fluoride (bp = -83 °C) polymerization occurs readily from a variety of alkyl, semifluorinated, and perfluorinated halides at 40 °C, in low-pressure glass tubes and in a variety of solvents, including water and alkyl carbonates. Perfluorinated alkyl iodide initiators also induce a controlled radical polymerization via iodine degenerative transfer (IDT). While IDT proceeds with accumulation of the less reactive P(m)-CF(2)-CH(2)-I vs the P(n)-CH(2)-CF(2)-I chain ends, Mn(2)(CO)(10) enables their subsequent quantitative activation toward the synthesis of well-defined poly(vinylidene fluoride) block copolymers with a variety of other monomers.