Chang Jun Jie, Pan Houwen Matthew, Goto Atsushi
Division of Chemistry and Biological Chemistry, School of Physical and Mathematical Sciences, Nanyang Technological University, 21 Nanyang Link, 637371, Singapore.
Chem Commun (Camb). 2021 Feb 2;57(9):1105-1108. doi: 10.1039/d0cc07987a.
In the presence of alkynes (CH[triple bond, length as m-dash]C-R2), iodide chain-end polymers (Polymer-I) were successfully transformed to vinyl iodide chain-end polymers (polymer-CH[double bond, length as m-dash]CR2-I) in a single step via organocatalysis. This reaction is completely metal-free and easy to carry out without using special reagents or special conditions. The polymers encompassing polyacrylates and polymethacrylate, and additional functionalities (e.g., OH and CF3) were also incorporated into the R2 moiety. The obtained Polymer-CH[double bond, length as m-dash]CR2-I further served as a useful precursor for copper-catalyzed cross-coupling reactions with various thiols (R3-SH) to yield vinyl sulfide chain-end polymers (polymer-CH[double bond, length as m-dash]CR2-SR3) with various R3 moieties. Interestingly, under selected conditions, this organocatalysis also offered block-like copolymers containing a conjugated oligo-alkyne segment and a non-conjugated polyacrylate segment. Exploiting the unique structure, the block-like copolymer was used as an efficient dispersant of carbon nanotubes.
在炔烃（CH≡C-R₂）存在的情况下，碘端基聚合物（聚合物-I）通过有机催化一步成功转化为乙烯基碘端基聚合物（聚合物-CH═CR₂-I）。该反应完全无金属，无需使用特殊试剂或特殊条件即可轻松进行。包含聚丙烯酸酯和聚甲基丙烯酸酯以及其他官能团（如OH和CF₃）的聚合物也被引入到R₂部分。所得到的聚合物-CH═CR₂-I进一步作为与各种硫醇（R₃-SH）进行铜催化交叉偶联反应的有用前体，以生成具有各种R₃部分的乙烯基硫醚端基聚合物（聚合物-CH═CR₂-SR₃）。有趣的是，在选定条件下，这种有机催化还提供了含有共轭低聚炔段和非共轭聚丙烯酸酯段的嵌段状共聚物。利用其独特结构，该嵌段状共聚物被用作碳纳米管的有效分散剂。
