Statistical copolymers of thiophene-3-carboxylates and selenophene-3-carboxylates; 77 Se NMR as a tool to examine copolymer sequence in selenophene-based conjugated polymers
Statistical copolymers of thiophene-3-carboxylates and selenophene-3-carboxylates; 77 Se NMR as a tool to examine copolymer sequence in selenophene-based conjugated polymers
复制标题
噻吩-3-羧酸酯和硒吩-3-羧酸酯的统计共聚物；
DOI：
10.1039/d2py00777k
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发表时间：
2022
影响因子：
4.6
通讯作者：
Noonan, Kevin J.
中科院分区：
文献类型：
--
作者：
Kawakami, Manami;Schulz, Karl H.;Varni, Anthony J.;Tormena, Claudio F.;Gil, Roberto R.;Noonan, Kevin J.
在此，我们证明了2-乙基己基噻吩-3-羧酸酯和2-乙基己基硒-3-羧酸酯单体的均聚和统计共聚是可能的通过铃木-宫浦交叉偶联。使用可商购的钯催化剂（[1，3-双（2，6-二-3-戊基苯基）咪唑-2-亚基]（3-氯吡啶基）二氯化钯（II）或PEPPSI-IPent）来制备具有高分子量（约20-30 kg mol-1）和相对窄的分子量分布的区域规则的共轭聚合物。通过增加材料中硒代-3-羧酸盐的浓度，可以降低共聚物系列中的光学带隙。在统计共聚物的1H NMR光谱中观察到了三单元体，其使用2D NMR技术的组合进行了分配。使用1H-77 Se HSQC光谱进一步检查统计共聚物中的序列分布，揭示了77 Se NMR如何可以用作检查含Se共轭聚合物的微观结构的工具。
Herein, we demonstrate that homopolymerization and statistical copolymerization of 2-ethylhexyl thiophene-3-carboxylate and 2-ethylhexyl selenophene-3-carboxylate monomers is possible via Suzuki–Miyaura cross-coupling. A commercially available palladium catalyst ([1,3-bis(2,6-di-3-pentylphenyl)imidazol-2-ylidene](3-chloropyridyl)dichloropalladium(II) or PEPPSI-IPent) was employed to prepare regioregular conjugated polymers with high molecular weights (∼20–30 kg mol−1), and relatively narrow molecular weight distributions. The optical bandgap in the copolymer series could be reduced by increasing the concentration of selenophene-3-carboxylate in the material. Configurational triads were observed in the 1H NMR spectra of the statistical copolymers, which were assigned using a combination of 2D NMR techniques. The use of a 1H–77Se HSQC spectrum to further examine sequence distribution in the statistical copolymers revealed how 77Se NMR can be used as a tool to examine the microstructure of Se-containing conjugated polymers.