Abstract

In this study, the molecular structure, prototropic behavior and supramolecular architecture of a new Schiff base have been studied in depth using spectroscopic (UV-vis), crystallographic (XRD) and computational (HOMA and DFT) methods. Regarding the molecular structure and prototropy, the XRD, DFT and HOMA results show that the compound exists in phenol-imine form. The HOMA indices for the structural evaluation show that the compound has a pure aromatic structure in solid state. UV-vis spectra of the compound dissolved in four different solvents were investigated in order to determine which tautomeric form of the compound is dominant in the solution. It is found that the compound prefers only phenol-imine form in apolar solvents while both phenol-imine and keto amine forms appear in polar solvents. This is because polar solvent decrease the activation energy, and thus, it becomes possible to observe both forms in the solution. For an energetic approach, the tautomeric conversion between two forms of the compound was investigated by a PES scan process and close energy values were obtained for two tautomers. Investigation of non-covalent interactions underlines the active roles of C–H···O H-bonds and C···Br interactions in constructing the supramolecular network of the compound.

中文翻译：

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（E）-4-溴-2-[[（苯基亚氨基）甲基] -5-甲氧基苯酚的分子结构，质子行为和超分子结构的分光光度法，晶体学和计算方法

摘要

在这项研究中，已使用光谱学（UV-vis），晶体学（XRD）和计算学（HOMA和DFT）方法对新型席夫碱的分子结构，质子行为和超分子结构进行了深入研究。关于分子结构和原生质，XRD，DFT和HOMA结果表明该化合物以苯酚-亚胺的形式存在。用于结构评估的HOMA指数表明该化合物具有固态的纯芳族结构。研究了溶解在四种不同溶剂中的化合物的紫外可见光谱，以确定该化合物的互变异构形式占主导地位。发现该化合物在非极性溶剂中仅优选苯酚-亚胺形式，而在极性溶剂中同时存在苯酚-亚胺和酮胺形式。这是因为极性溶剂降低了活化能，因此可以观察溶液中的两种形式。对于能量方法，通过PES扫描方法研究了两种形式的化合物之间的互变异构转化，并获得了两个互变异构体的接近能量值。对非共价相互作用的研究强调了C–H··O H键和C··Br相互作用在构建该化合物的超分子网络中的积极作用。