Catalytic Cyclopropanation of Polybutadienes
نویسندگان
چکیده
Catalytic cyclopropanation of commercial 1,2or 1,4cis-polybutadiene, respectively, with ethyl diazoacetate catalyzed by [TpCu(NCMe)] (Tp 1⁄4 hydrotris(3,4,5-tribromo-1-pyrazolyl)borate) at room temperature afforded high molecular weight (Mn > 10 5 mol ) side-chain or main-chain, respectively, carboxyethyl cyclopropyl-substituted polymers with variable and controlled degrees of functionalization. Complete functionalization of 1,4-cis-polybutadiene afforded poly[ethylene-alt-(3-ethoxycarbonyl-cyclopropene)]. Catalytic hydrogenation of residual double bonds of partially cyclopropanated polybutadienes provided access to the corresponding saturated polyolefins. Thermal properties are reported.
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