Bimetallic catalysts have shown promise for improving polar comonomer incorporation by late transition metals, but such effects are underexplored using early transition metal catalysts. Herein, the copolymerization of ethylene and α-olefins bearing alcohol groups was performed using mono- and dizirconium bisamine bisphenolate catalysts in the presence of MAO and Al i Bu3. Under these conditions, catalyst activity was retained with comonomer incorporation trends mirroring those observed with unfunctionalized α-olefins, i.e., lower incorporation by bimetallic catalysts. Although incorporation levels are low, these data provide mechanistic insight for polar comonomer incorporation. These results are consistent with our earlier proposal that larger comonomers sterically clash with the distal metal center of the bimetallic catalysts, leading to lower incorporation. Additionally, a bimetallic mechanism for polar comonomer coordination and incorporation is not supported by the current data.

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The synthesis and characterization of a series of cyclometallated complexes of Pd(ii) incorporating the mixed donor ligand 1-oxa-4,7-dithiacyclononane ([9]aneS2O) are presented in this study.

Linear α-olefins are accessed efficiently from ethylene in the Shell higher olefin process (SHOP), an industrial process practiced on a million-ton scale that generates a statistical mixture of C 4 -C 30 products. An analogous general process for the preparation of a range of α,ω-dienes is lacking. We herein report a two-step method that generates industrially relevant α,ω-dienes. In the first step, ethylene and butadiene are copolymerized to generate copolymers with a variable butadiene content. A titanium bisphenoxide bisthiolate catalyst activated with methylaluminoxane (MAO) was selected for this step due to the high selectivity for 1,4-butadiene incorporation. Ethenolysis of the copolymers results in a distribution of α,ω-dienes in the C 10 -C 20 range. Depending on the conditions, linear trienes are also generated. The reported protocol provides a strategy for copolymer upcycling to value-added olefin products.