Air-Stable (Phenylbuta-1,3-diynyl)palladium(II) Complexes: Highly Active Initiators for Living Polymerization of Isocyanides
Air-Stable (Phenylbuta-1,3-diynyl)palladium(II) Complexes: Highly Active Initiators for Living Polymerization of Isocyanides
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空气稳定的 (Phenylbuta-1,3-diynyl)pald(II) 配合物：异氰化物活性聚合的高活性引发剂
DOI：
10.1021/ja5004747
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发表时间：
2014-03-26
影响因子：
15
通讯作者：
Wu, Zong-Quan
中科院分区：
文献类型：
--
作者：
Xue, Ya-Xin;Zhu, Yuan-Yuan;Wu, Zong-Quan
设计并合成了一类空气稳定的苯基丁二炔钯配合物。其结构经H-1和C-13 NMR、MS和X-射线分析表征。这些钯配合物被发现有效地引发聚合的苯基异腈在一个活的/可控的链增长的方式，这导致形成聚（苯基异腈）与控制的分子量和窄的分子量分布。~（13）C NMR分析表明，聚苯基异腈具有较高的立构规整性.聚合物链末端的Pd单元可以与苯基异腈单体进一步共聚得到嵌段共聚物。在钯配合物的苯基上引入给电子基团可以提高催化活性。此外，这些Pd配合物耐受大多数有机溶剂，并适用于广泛的异氰化物单体，包括烷基和苯基异氰化物，甚至在邻位具有庞大取代基的苯基异氰化物和二异氰化物单体。因此，该聚合体系在制备具有受控序列的明确定义的聚异腈中是通用的。设计并合成了两个和三个Pd单元的双官能和三官能Pd配合物。它们还能够引发苯基异氰化物的活性聚合，以提供具有可控分子量和窄分子量分布的遥爪线性和星形聚异氰化物。
A family of air-stable (phenylbuta-1,3-diynyl)palladium(II) complexes were designed and prepared in a facile synthetic procedure. Their structures were characterized by H-1 and C-13 NMR, MS, and X-ray analysis. These Pd complexes were revealed to efficiently initiate the polymerization of phenyl isocyanides in a living/controlled chain growth manner, which led to the formation of poly(phenyl isocyanide)s with controlled molecular weights and narrow molecular weight distributions. C-13 NMR analysis indicated the isolated poly(phenyl isocyanide) was of high stereoregularity. The Pd unit at the end of the polymer chain could undergo further copolymerization with phenyl isocyanide monomers to give block copolymers. It was also found that incorporation of an electron-donating group on the phenyl group of the Pd complex could improve the catalytic activities. Furthermore, these Pd complexes were tolerant to most organic solvents and applicable to a wide range of isocyanide monomers including alkyl and phenyl isocyanides and even phenyl isocyanide with bulky substituents at the ortho position and diisocyanide monomers. Therefore, this polymerization system is versatile in the preparation of well-defined polyisocyanides with controlled sequence. Bi- and trifunctional Pd complexes with two and three Pd units incorporated onto the same phenyl ring were designed and synthesized. They were also able to initiate the living polymerization of phenyl isocyanide to afford telechelic linear and star-shaped polyisocyanides with controlled molecular weights and narrow molecular weight distributions.