Radical Coordination Chemistry and Its Relevance to Metal‐Mediated Radical Polymerization (Eur. J. Inorg. Chem. 10/2011)

Abstract

AbstractThe cover picture shows two different and interplaying processes involving a metal complex and organic radicals, which play a key role in the controlled radical polymerization of vinyl acetate by what has been termed “Organometallic Mediated Radical Polymerization” (OMRP). Bis(acetylacetonato)cobalt(II), Co(acac)2, reversibly adds the growing radical chain (symbolized by “M + R�”) to form a dormant metal‐capped (acac)2Co–PVAc chain (“M–R”), which contains a thermally fragile metal–carbon bond. The latter, however, in addition to the reversible radical chain dissociation, can also undergo an associative radical‐chain exchange through a transition state symbolized as “R···M···R”. This is just one example of how one‐electron processes involving metal complexes and radicals play a fundamental role in radical polymerization. It is the topic of the Microreview by R. Poli on p. 1513 ff, covering the coordination chemistry of organic radicals and its relevance to metal‐mediated radical polymerization. The background image represents a random conformation of a poly(vinyl acetate) chain segment.