π共轭纳米带由于其不寻常的电子结构和电荷传输行为而引起人们的兴趣。这里,我们报道了一系列完全边缘融合的卟啉-蒽低聚带(二聚体和三聚体)的合成,以及相应的无限聚合物的计算研究。高收率合成了卟啉二聚体和三聚体,通过单连接前体的氧化环化脱氢,使用2,3-二氯-5,6-二氰基-1,4-苯醌(DDQ)和三氟甲磺酸(TfOH)。二聚体的晶体结构表明,中心π系统是平坦的,每个卟啉末端都有轻微的S形波失真。扩展的π-共轭引起吸收光谱的显着红移:融合的二聚体和三聚体的吸收最大值出现在1188nm和1642nm,分别(对于溶解在甲苯中的镍络合物)。二聚体中的配位金属由Ni变为Mg,使用对甲苯基溴化镁,提供获得游离碱和Zn络合物。这些结果为具有集成金属卟啉单元的更长的π共轭纳米带开辟了一条通用的途径。
π-Conjugated nanoribbons attract interest because of their unusual electronic structures and charge-transport behavior. Here, we report the synthesis of a series of fully edge-fused porphyrin-anthracene oligomeric ribbons (dimer and trimer), together with a computational study of the corresponding infinite polymer. The porphyrin dimer and trimer were synthesized in high yield, via oxidative cyclodehydrogenation of singly linked precursors, using 2,3-dichloro-5,6-dicyano-1,4-benzoquinone (DDQ) and trifluoromethanesulfonic acid (TfOH). The crystal structure of the dimer shows that the central π-system is flat, with a slight S-shaped wave distortion at each porphyrin terminal. The extended π-conjugation causes a dramatic red-shift in the absorption spectra: the absorption maxima of the fused dimer and trimer appear at 1188 nm and 1642 nm, respectively (for the nickel complexes dissolved in toluene). The coordinated metal in the dimer was changed from Ni to Mg, using p-tolylmagnesium bromide, providing access to free-base and Zn complexes. These results open a versatile avenue to longer π-conjugated nanoribbons with integrated metalloporphyrin units.