Jaye Joseph A, Sletten Ellen M
Department of Chemistry and Biochemistry, University of California, Los Angeles, California 90095, United States.
ACS Macro Lett. 2020 Mar 17;9(3):410-415. doi: 10.1021/acsmacrolett.9b00979. Epub 2020 Feb 28.
Postpolymerization modifications are a prominent route for tuning polymer properties and diversifying materials. Thus, polymers containing robust chemical handles are desirable. Vinyl iodide functionality is commonly enlisted for selective transformations on small molecules, but these chemistries, while efficient enough for postpolymerization modifications, are less frequently performed on macromolecules due to limited methods to install vinyl iodide groups into polymers. Here, we present an iodo-yne polymerization involving diynes and diiodoperfluoroalkanes to facilely give semifluorinated polymers with vinyl iodide groups throughout the polymer chain. The iodo-yne polymerization yields polymers of at least 6 kDa while open to air in aqueous solvent. We demonstrate that the iodo-yne polymers can be modified at the vinyl iodide functionality via a variety of metal-catalyzed cross-coupling reactions. Additionally, the iodide can be eliminated to give electronically activated alkynes that can undergo cycloaddition with azides. Taken together, this work will push the current boundaries of functional polymers and assist in the development of modernized, smart materials.
聚合后修饰是调节聚合物性能和使材料多样化的一条重要途径。因此，含有稳定化学官能团的聚合物是理想的。乙烯基碘官能团通常用于小分子的选择性转化，但这些化学方法虽然对聚合后修饰足够有效，但由于将乙烯基碘基团引入聚合物的方法有限，在大分子上的应用较少。在此，我们展示了一种涉及二炔和二碘全氟烷烃的碘-炔聚合反应，可轻松得到在整个聚合物链中带有乙烯基碘基团的半氟化聚合物。碘-炔聚合反应在水性溶剂中暴露于空气中时可生成至少6 kDa的聚合物。我们证明，碘-炔聚合物可通过多种金属催化的交叉偶联反应在乙烯基碘官能团处进行修饰。此外，碘化物可以被消除，得到可与叠氮化物发生环加成反应的电子活化炔烃。综上所述，这项工作将突破功能聚合物的现有界限，并有助于现代化智能材料的开发。
