Scalable Synthesis of Bio-Based Functional Styrene: Protected Vinyl Catechol from Caffeic Acid and Controlled Radical and Anionic Polymerizations Thereof
Scalable Synthesis of Bio-Based Functional Styrene: Protected Vinyl Catechol from Caffeic Acid and Controlled Radical and Anionic Polymerizations Thereof
复制标题
生物基功能苯乙烯的可规模化合成：受咖啡酸保护的乙烯基儿茶酚及其受控自由基和阴离子聚合
DOI：
10.1021/acssuschemeng.8b04400
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发表时间：
2018
影响因子：
8.4
通讯作者：
Masami Kamigaito
中科院分区：
文献类型：
--
作者：
Hisaaki Takeshima;Kotaro Satoh;Masami Kamigaito
天然丰富的咖啡酸是一种肉桂酸衍生物，其结构中含有儿茶酚基团，通过易于扩展的脱羧和保护反应，可定量转化为一系列受保护的乙烯基儿茶酚（VC）衍生物。使用适当的可逆加成-裂解链转移剂或烷氧胺，受保护的vc进行了可控的自由基聚合，生成了定义明确的聚合物，尽管所获得的聚合物的反应速率和分子量分布取决于单体上的保护基团。在- 78°C的THF中，以叔丁基锂为引发剂，在适当的保护基团（- SiMe2tBu或- SiiPr3）下也实现了vc的阴离子聚合。此外，通过改变聚合条件和阴离子聚合中单体上的保护基团，可以控制聚合物的聚合策略。
Naturally abundant caffeic acid, a cinnamic acid derivative with a catechol group in its structure, was quantitatively converted into a series of protected vinyl catechol (VC) derivatives via facile and scalable decarboxylation and protection reactions. Controlled radical polymerizations of the protected VCs proceeded well using the appropriate reversible addition–fragmentation chain transfer agent or alkoxyamine to generate well-defined polymers, although the reaction rates and molecular weight distributions of the obtained polymers were dependent on the protecting groups on the monomers. Anionic polymerizations of the VCs were also achieved with the appropriate protecting groups (−SiMe2tBu or −SiiPr3) usingsec-butyllithium as an initiator in THF at −78 °C. Furthermore, the tacticities of the obtained polymers could be controlled by varying the conditions of the polymerizations and the protecting groups on the monomers in the anionic polymerization.