Synthesis, Characterization, and Properties of Poly(aryl)phosphinoboranes Formed via Iron-Catalyzed Dehydropolymerization
Synthesis, Characterization, and Properties of Poly(aryl)phosphinoboranes Formed via Iron-Catalyzed Dehydropolymerization
复制标题
铁催化脱氢聚合形成的聚(芳基)膦硼烷的合成、表征和性能
DOI：
10.1002/macp.201700120
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发表时间：
2017
影响因子：
2.5
通讯作者：
Turner J
中科院分区：
文献类型：
--
作者：
Turner J
以富含稀土元素Fe为催化剂，考察了伯膦-硼烷RPH2·BH3(1a-f)(R=3，4-(OCH2O)C6H3(A)，Ph(B)，p-(CF3O)C6H4(C)，3，5-(CF3)2C6H3(D)，2，4，6-(CH3)3C6H2(E)，2，4，6-tBu3C6H2(F))的脱氢聚合反应。多核核磁共振谱证实了多膦硼烷[RPh-BH2]n(2a-e)的形成，但没有检测到1f2转化为2f.电喷雾电离质谱仪的分析证实了2a-e的预期聚合物重复单元的存在。凝胶渗透色谱(GPC)证实了2a-e的聚合性质，并表明数均相对分子质量(Mn)为12 000-209 000 Da，多分散性指数在1.14至2.17之间。相比之下，在没有添加预催化剂的情况下，1a-eE的热脱氢聚合会导致低聚物的形成。有趣的是，多膦硼烷2and2d表现出典型的聚电解质的GPC行为，其流体动力学半径依赖于浓度。研究了薄膜的热转变行为、热稳定性和表面性质。
The dehydropolymerization of the primary phosphine–boranes, RPH2•BH3(1a–f) (R = 3,4‐(OCH2O)C6H3(a), Ph (b),p‐(CF3O)C6H4(c), 3,5‐(CF3)2C6H3(d), 2,4,6‐(CH3)3C6H2(e), 2,4,6‐tBu3C6H2(f)) is explored using the precatalyst [CpFe(CO)2OTf] (I) (OTf = OS(O)2CF3), based on the earth abundant element Fe. Formation of polyphosphinoboranes [RPH‐BH2]n(2a–e) is confirmed by multinuclear NMR spectroscopy, but no conversion of1fto2fis detected. Analysis by electrospray ionization mass spectrometry confirms the presence of the anticipated polymer repeat units for2a–e. Gel permeation chromatography (GPC) confirms the polymeric nature of2a–eand indicates number‐average molecular weights (Mn) of 12 000–209 000 Da and polydispersity indices between 1.14 and 2.17. By contrast, thermal dehydropolymerization of1a–ein the absence of added precatalyst leads to formation of oligomeric material. Interestingly, polyphosphinoboranes2cand2ddisplay GPC behavior typical of polyelectrolytes, with a hydrodynamic radius dependent on concentration. The thermal transition behavior, thermal stability, and surface properties of thin films are also studied.