Hussein M A, Osman O I, Asiri A M, Rozman H D, El-Daly S A
Department of Chemistry, Faculty of Science, King Abdulaziz University, P.O. Box 80203, Jeddah, 21589, Saudi Arabia.
Chemistry Department, Faculty of Science, Assiut University, Assiut, 71516, Egypt.
J Fluoresc. 2017 May;27(3):1129-1140. doi: 10.1007/s10895-017-2048-8. Epub 2017 Feb 23.
Diarylidenecyclopentanone compound namely, 2,5-bis[4-choloroacetyl-(thiophen-2-ylmethylene)]cyclopentanone (BCTCP) was firstly synthesized using the normal condition of Friedel-Crafts method by reacting 2,5-bis(thiophen-2-ylmethylene)cyclopentanone (BTCP) with chloroacetyl chloride in the presence of aluminum chloride anhydrous. The structure of this compound was confirmed by elemental and spectral analyses including FT-IR, H-NMR, C-NMR and mass spectrometry. The electronic absorption and emission properties of BCTCP were studied in different solvents. BCTCP displays a slight solvatochromic effect of the absorption and emission spectrum, indicating a small change in dipole moment of BCTCP upon excitation. BCTCP displayed photodecomposition in chlorinated solvents upon irradiating with 365 nm light. Ground and excited states electronic geometric optimizations were performed using density functional theory (DFT) and time-dependent density functional theory (TD-DFT), respectively. A DFT natural bond orbital (NBO) analysis complemented the intramolecular charge transfer (ICT). The simulated maximum absorption and emission wavelengths are in line the observed ones in trend, and were proportionally red-shifted with the increase of the solvent polarity. The stability, hardness and electrophilicity of BCTCP in different solvents were correlated with the polarity of the elected solvents.
二芳叉环戊酮化合物，即2,5-双[4-氯乙酰基-（噻吩-2-基亚甲基）]环戊酮（BCTCP），首先在无水氯化铝存在下，通过弗瑞德-克来福特法的常规条件，使2,5-双（噻吩-2-基亚甲基）环戊酮（BTCP）与氯乙酰氯反应合成得到。该化合物的结构通过元素分析和光谱分析得以确认，包括傅里叶变换红外光谱（FT-IR）、氢核磁共振谱（H-NMR）、碳核磁共振谱（C-NMR）和质谱分析。研究了BCTCP在不同溶剂中的电子吸收和发射特性。BCTCP在吸收和发射光谱上表现出轻微的溶剂化显色效应，表明激发时BCTCP的偶极矩变化较小。用365 nm光照射时，BCTCP在氯化溶剂中发生光分解。分别使用密度泛函理论（DFT）和含时密度泛函理论（TD-DFT）对基态和激发态进行电子几何优化。DFT自然键轨道（NBO）分析补充了分子内电荷转移（ICT）。模拟的最大吸收和发射波长在趋势上与观测值一致，并且随着溶剂极性的增加而按比例红移。BCTCP在不同溶剂中的稳定性、硬度和亲电性与所选溶剂的极性相关。
