Interfacial behaviors and aggregate structure of atropisomers of picket-fence porphyrin at the air/water interface
Interfacial behaviors and aggregate structure of atropisomers of picket-fence porphyrin at the air/water interface
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栅栏卟啉阻转异构体在空气/水界面的界面行为和聚集结构
DOI：
10.1016/j.colsurfa.2010.12.050
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发表时间：
2011
期刊：
影响因子：
--
通讯作者：
Ying Hu
中科院分区：
文献类型：
--
作者：
Zhenfeng Cao;Qibin Chen;Chaowei Wang;Y. Ren;Honglai Liu;Ying Hu
我们合成了新戊酰胺苯基取代的卟啉的四种阻转异构体：α,α,α,β-PivPP（内消旋-α,α,α,β-四（邻新戊酰胺苯基）卟啉的缩写）、α,β,α,β-PivPP、α,α,β,β-PivPP 和 α,α,α,α-PivPP。后一种通常称为“栅栏”取代卟啉。使用 Langmuir-Blodgett (LB) 技术、紫外可见 (UV-vis) 和原子力显微镜 (AFM) 研究了四种化合物的界面行为。获得的 π-A 等温线表明，PivPP 的 Langmuir 单层是在空气/水界面形成的，但 α,α,β,β-PivPP 除外，它在 11-14mN/m 范围内的表面压力下表现出一个平台，表明单层转变。紫外可见光谱显示，与稀释的氯仿溶液中的相应吸收带相比，沉积在石英载玻片上的四种阻转异构体LB薄膜的卟啉Soret带发生红移，这是由于卟啉环之间强烈的π-π相互作用造成的。除α,α,β,β-PivPP外，AFM图像还表明取代卟啉阻转异构体形成的LB膜是均质的单层。一般来说，在压缩单分子层的过程中，成膜分子堆积得更紧密，这与LB膜的吸收强度增强且Soret带随着表面压力的增加而变化的紫外-可见光谱结果一致。另一方面，α,α,β,β-PivPP 在较高表面压力下的 AFM 形貌表明形成了双层，这与 π-A 等温线中平台的存在相一致。
We have synthesized four atropisomers of the pivalamido phenyl substituted porphyrins, α,α,α,β-PivPP (abbreviation of meso-α,α,α,β-tetra(o-pivalamidophenyl)porphyrin), α,β,α,β-PivPP, α,α,β,β-PivPP and α,α,α,α-PivPP. The latter one is usually called the “picket-fence” substituted porphyrin. The interfacial behaviors of the four compounds have been studied by using Langmuir–Blodgett (LB) technique, Ultraviolet–visible (UV–vis) and Atomic Force Microscopy (AFM). The obtained π–A isotherms show that the Langmuir monolayers of PivPPs are formed at the air/water interface except that of α,α,β,β-PivPP which exhibits a platform at the surface pressure in the range of 11–14mN/m indicating a monolayer transition. The UV–vis spectra disclose that the red-shift happens in the porphyrin Soret bands of the four atropisomer LB films deposited on quartz slides compared with the corresponding absorption bands in the diluted chloroform solution, which results from the strong π–π interaction between porphyrin rings. Except for α,α,β,β-PivPP, AFM images also suggest that the LB films formed by atropisomers of the substituted porphyrin are homogeneous monolayer. Generally, film-forming molecules pack more tightly during compressing the mononlayers, which is consistent with the UV–vis spectra results that the absorption intensities of LB films enhance and the Soret band varies with the increase of surface pressure. On the other hand, AFM morphologies of α,α,β,β-PivPP at higher surface pressure reveal that bilayers are formed, which coincides with the presence of a platform in the π–A isotherm.
影响因子：
3.9
作者：
T. Kawai;J. Umemura;T. Takenaka
通讯作者：
T. Kawai;J. Umemura;T. Takenaka