Universal Suzuki-Miyaura Catalyst-Transfer Polymerization for Precision Synthesis of Strong Donor/Acceptor-Based Conjugated Polymers and Their Sequence Engineering
Universal Suzuki-Miyaura Catalyst-Transfer Polymerization for Precision Synthesis of Strong Donor/Acceptor-Based Conjugated Polymers and Their Sequence Engineering
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DOI：
10.1021/jacs.1c05080
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发表时间：
2021-07-15
影响因子：
15
通讯作者：
Choi, Tae-Lim
中科院分区：
文献类型：
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作者：
Lee, Jaeho;Kim, Hwangseok;Choi, Tae-Lim
催化剂转移聚合以其活性特征使聚合物合成领域发生了革命性的变化，但对于特定的催化剂体系，聚合物的范围相当狭窄。本文报道了一种高效的Suzuki-Miyaura催化剂转移聚合（SCTP），通过合理设计硼酸酯单体和使用市售的Buchwald RuPhos和SPhos Pd G3预催化剂，该聚合反应涵盖了从富电子（供体，D）到缺电子（受体，A）（杂）芳烃的广泛单体。首先，我们通过引入新的硼酸酯，如4，4，8，8-四甲基-1，3，6，2-二氧氮杂硼杂环辛烷及其N-苄基化衍生物来调节单体的反应性和稳定性，优化了3，4-丙烯二氧噻吩（ProDOT）、苯并三唑（BTz）、喹喔啉（QX）和2，3-二苯基喹喔啉（QXPh）的可控聚合。结果，以优异的产率（>85%）制备了具有可控分子量和窄分散性（D < 1.29）的PProDOT、PBTz、PQX和PQXPh。使用H-1 NMR和MALDI-TOF光谱的聚合物结构的详细调查支持链增长机制和高引发效率的SCTP方法。此外，RuPhos-Pd在两种D/A单体上显示出优异的催化剂转移能力，导致前所未有的受控D-A统计共聚，从而调节所得共聚物的HOMO能级（从-5.11至-4.80 eV）和带隙能量（从1.68至1.91 eV）。此外，为了证明SCTP的活性性质，通过顺序添加方法成功地制备了D-A和A-A嵌段共聚物（PBTz-b-PProDOT、PQX-b-PProDOT和PQX-b-PBTz）的各种组合。最后，通过最大化快速增长的频哪醇硼酸酯给体和缓慢增长的受体之间的速率差来实现简单但强大的一次D-A嵌段共聚，以提供定义明确的聚（3-己基噻吩）-b-聚（苯并三唑）。
Catalyst-transfer polymerization has revolutionized the field of polymer synthesis due to its living character, but for a given catalyst system, the polymer scope is rather narrow. Herein we report a highly efficient Suzuki-Miyaura catalyst-transfer polymerization (SCTP) that covers a wide range of monomers from electron-rich (donor, D) to electron-deficient (acceptor, A) (hetero)arenes by rationally designing boronate monomers and using commercially available Buchwald RuPhos and SPhos Pd G3 precatalysts. Initially, we optimized the controlled polymerization of 3,4-propylenedioxythiophene (ProDOT), benzotriazole (BTz), quinoxaline (QX), and 2,3-diphenylquinoxaline (QXPh) by introducing new boronates, such as 4,4,8,8-tetramethy1-1,3,6,2-dioxazaborocane and its N-benzylated derivative, to modulate the reactivity and stability of the monomers. As a result, PProDOT, PBTz, PQX, and PQXPh were prepared with controlled molecular weight and narrow dispersity (D < 1.29) in excellent yield (>85%). A detailed investigation of the polymer structures using H-1 NMR and MALDI-TOF spectrometry supported the chain-growth mechanism and the high initiation efficiency of the SCTP method. In addition, the use of RuPhos-Pd showing excellent catalyst-transfer ability on both D/A monomers led to unprecedented controlled D-A statistical copolymerization, thereby modulating the HOMO energy level (from -5.11 to -4.80 eV) and band gap energy (from 1.68 to 1.91 eV) of the resulting copolymers. Moreover, to demonstrate the living nature of SCTP, various combinations of D -A and A-A block copolymers (PBTz-b-PProDOT, PQX-b-PProDOT, and PQX-b-PBTz) were successfully prepared by the sequential addition method. Finally, simple but powerful one-shot D-A block copolymerization was achieved by maximizing the rate difference between a fast-propagating pinacol boronate donor and a slow-propagating acceptor to afford well-defined poly(3-hexylthiophene)-b-poly(benzotriazole).