Scope and Regioselectivity of Iridium-Catalyzed C–H Borylation of Aromatic Main-Chain Polymers
作者:Ying Chang、Hanniel H. Lee、Se Hye Kim、Tae Soo Jo、Chulsung Bae
DOI:10.1021/ma302588a
日期:2013.3.12
pinacolborane. The regioselectivity of the borylation was investigated using model compounds that mimic the repeating unit structure of poly(arylene ether sulfone). The C–H bonds of the sulfone model compound were more reactive than those of the bisphenol model compound, and the borylation occurred preferentially at the meta position to the sulfone moiety owing to steric hindrance and electronic effects
芳香族主链聚合物的有效官能化是通过铱催化的芳香族C–H键的硼化和Suzuki–Miyaura偶联反应的结合而建立的。各种铱催化剂和硼化试剂的比较研究表明[Ir(OMe)(COD)] 2的活性明显高于[IrCl(COD)] 2的活性,而bis(pinacolato)diboron的效率高于pinacolborane。使用模拟聚(亚芳基醚砜)的重复单元结构的模型化合物研究了硼酸酯化的区域选择性。砜类化合物的C–H键比双酚类化合物的C–H键更具反应性,由于空间位阻和电子效应,硼化反应优先发生在砜部分的间位。硼酸化的聚合物的玻璃化转变温度随着频哪醇硼酸酯基团浓度的增加而增加。频哪醇硼酸酯基团可以方便地转化为硼酸[B(OH)2 ]和三氟硼酸钾(BF 3K),也可以用作通过Suzuki-Miyaura偶联合成各种功能化聚合物的多功能反应位点。