p-Cymene: A Sustainable Solvent that is Highly Compatible with Direct Arylation Polymerization (DArP)
p-Cymene: A Sustainable Solvent that is Highly Compatible with Direct Arylation Polymerization (DArP)
复制标题
对伞花烃：一种与直接芳基化聚合 (DArP) 高度兼容的可持续溶剂
DOI：
10.1021/acsmacrolett.1c00274
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发表时间：
2021
影响因子：
7.015
通讯作者：
Thompson, Barry C.
中科院分区：
文献类型：
--
作者：
Ye, Liwei;Thompson, Barry C.
十多年来，直接芳基化聚合（DArP）已被证明是一种环保，简便，低成本的替代传统方法，如用于共轭聚合物合成的Stille聚合。通过C-H活化途径，DArP减少了合成步骤，同时消除了化学计量的高毒性有机锡副产物的产生。然而，作为这些反应中的主要组分，DArP最常用的溶剂是危险的并且由不可持续的来源产生，例如二甲基乙酰胺（DMA）、四氢呋喃（THF）和甲苯。尽管最近出现了可持续替代溶剂如2-MeTHF和环戊基甲基醚（CPME）的使用，但醚溶剂的缺点包括需要加压反应装置以及潜在的过氧化物形成。虽然芳族溶剂在溶解共轭聚合物方面是上级的，但在寻找这类溶剂的更可持续的、良性的替代品方面做得很少。在此，我们首次报道了一种可持续的、天然来源的、高沸点芳香族溶剂对伞花烃在DArP中的应用。对伞花烃在合成大范围的交替共聚物中表现出优异的增溶能力，Mn可达51.3kg/mol，产率可达96.2%，优于CPME和甲苯合成的共聚物。结构分析揭示了使用对伞花烃作为溶剂制备的这些聚合物中的缺陷的排除，在2，2 ′-联噻吩单体的情况下，通过使用用于DArP的常规溶剂（例如DMA和甲苯）来获得对伞花烃是具有挑战性的。
For over a decade, Direct Arylation Polymerization (DArP) has been demonstrated to be an eco-friendly, facile, and low-cost alternative to conventional methodologies such as Stille polymerization for conjugated polymer synthesis. By accessing through a C–H activation pathway, DArP offers a reduction of synthetic steps while eliminating the generation of stoichiometric, highly toxic organotin byproducts. However, as the major component in these reactions, the solvents most prevalently employed for DArP are hazardous and produced from unsustainable sources, such as dimethylacetamide (DMA), tetrahydrofuran (THF), and toluene. Although the use of sustainable alternative solvents such as 2-MeTHF and cyclopentyl methyl ether (CPME) has recently emerged, drawbacks of ethereal solvents include the need for a pressurized reaction setup as well as potential peroxide formation. While aromatic solvents are superior in solubilizing conjugated polymers, very little has been done in searching for more sustainable, benign alternatives for this class of solvent. Herein, we report the application of a sustainable, naturally sourced, high-boiling aromatic solvent, p-cymene, to DArP for the first time. p-Cymene was found to display excellent solubilizing ability in the synthesis of a broad scope of alternating copolymers withMnup to 51.3 kg/mol and yields up to 96.2%, outperforming those prepared using CPME and toluene. Structural analysis revealed the exclusion of defects in these polymers prepared using p-cymene as the solvent which, in the case of a 2,2′-bithiophene monomer, is challenging to access through the use of conventional solvents for DArP, such as DMA and toluene.