Elshakre Mohamed E, Moustafa H, Hassaneen Huwaida M E, Moussa Abdelrahim Z
Chemistry Department, College of Science, Cairo University, University Ave., Dokki, 12613 Cairo, Egypt.
Chemistry Department, College of Science, Cairo University, University Ave., Dokki, 12613 Cairo, Egypt.
Spectrochim Acta A Mol Biomol Spectrosc. 2015 Jun 15;145:1-14. doi: 10.1016/j.saa.2015.02.107. Epub 2015 Mar 2.
Ground state properties of 2,4-diphenyl-1,4-dihydrobenzo[4,5]imidazo[1,2-a]pyrimidine, compound 1, and its derivatives are investigated experimentally and theoretically in Dioxane and DMF. The calculations show that all the studied compounds (1-7) are non-planar, resulting in a significant impact on the electronic and structural properties. The ground state properties of compounds 1-7 at B3LYP/6-311G (d, p) show that compound 5 has the lowest EHOMO, ELUMO, and ΔE indicating highest reactivity. Compound 7 is found to have the highest polarity. The observed UV spectra in Dioxane and DMF of compounds 1-4 show 2 bands, while compounds 5-7 show 4 bands in both solvents. Band maxima (λmax) and intensities of the spectra are found to have solvent dependence reflected as blue and red shifts. The theoretical spectra computed at TD-B3LYP/6-311G (d, p) in gas phase, Dioxane and DMF indicate a good agreement with the observed spectra.
在二氧六环和N,N-二甲基甲酰胺中，通过实验和理论方法研究了2,4-二苯基-1,4-二氢苯并[4,5]咪唑并[1,2-a]嘧啶（化合物1）及其衍生物的基态性质。计算结果表明，所有研究的化合物（1-7）均为非平面结构，这对其电子和结构性质产生了显著影响。在B3LYP/6-311G(d,p)水平下对化合物1-7基态性质的研究表明，化合物5具有最低的最高占据分子轨道能量（EHOMO）、最低未占据分子轨道能量（ELUMO）和能隙（ΔE），表明其具有最高的反应活性。发现化合物7具有最高的极性。在二氧六环和N,N-二甲基甲酰胺中观察到的化合物1-4的紫外光谱显示有2个吸收带，而化合物5-7在这两种溶剂中均显示有4个吸收带。发现光谱的最大吸收峰（λmax）和强度具有溶剂依赖性，表现为蓝移和红移。在气相、二氧六环和N,N-二甲基甲酰胺中，采用TD-B3LYP/6-311G(d,p)计算得到的理论光谱与观察到的光谱吻合良好。
