| Abstract
| - Unprecedented rhodium-catalyzed stereoselective polymerization of “carbenes” from ethyldiazoacetate (EDA) to give high molecular mass poly(ethyl 2-ylidene-acetate) is described. The mononuclear,neutral [(N,O-ligand)MI(cod)] (M = Rh, Ir) catalytic precursors for this reaction are characterized by (amongothers) single-crystal X-ray diffraction. These species mediate formation of a new type of polymers fromEDA: carbon-chain polymers functionalized with a polar substituent at each carbon of the polymer backbone.The polymers are obtained as white powders with surprisingly sharp NMR resonances. Solution and solidstate NMR data for these new polymers reveal a highly stereoregular polymer, with a high degree ofcrystallinity. The polymer is likely syndiotactic. Material properties are very different from those of atacticpoly(diethyl fumarate) polymer obtained by radical polymerization of diethyl fumarate. Other diazoacetatesare also polymerized. Further studies are underway to reveal possible applications of these new materials.
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