Development of polymer syntheses using diazocarbonyl compounds as monomers

Abstract

Recent results from the author’s research group on the development of polymer syntheses using diazocarbonyl compounds as monomers are described. A series of new Pd-based initiating systems for C1 polymerization of diazoacetate have been developed, each of which possesses characteristic initiating ability with respect to high-molecular-weight polymer synthesis, tacticity control, and chain end functionalization. The use of functional ester substituents has led to polymers with unique properties and functionalities in comparison to their vinyl polymer counterparts [poly(alkyl acrylate)] with the same ester substituent. Polycondensations using bis(diazocarbonyl) compounds as monomers are also described. By utilizing a variety of reactivities of a diazocarbonyl group, a series of three-, two-, and single-component polycondensations have been realized, affording new polymers whose chemical structures cannot be attained by any existing method for polymer syntheses. Polymer syntheses utilizing diazocarbonyl compounds as monomers are described. Pd-based initiators active for the C1 polymerization of diazoacetates have been developed; the presence of η3-type anionic ligand on the Pd center has been proved to be essential for the initiator to be highly active for the polymerization. Pd complexes bearing naphthoquinone or its derivatives as a ligand were effective for the initiator generation in conjunction with NaBPh4. By using a series of bis(diazocarbonyl) compounds as monomers, three-, two-, and single-component polycondensations have been newly developed, affording unprecedented polymer structures.