Synthesis, crystal structure, and spectroscopic properties of new stilbazolium salt with enlarged ¦Ð-conjugated system

详细信息    查看全文

• 作者：Mina Todorova ^{mtodorova@uni-plovdiv.bg} ; Rumyana Bakalska ^{bakalska@uni-plovdiv.bg} ; Tsonko Kolev ; ^{kolev@uni-plovdiv.bg}
• 关键词：Stilbazolium dye ; Synthesis ; Crystal structure ; Optical properties ; Vibrational spectra ; Quantum chemical calculations
• 刊名：Spectrochimica Acta Part A: Molecular and Biomolecular Spectroscopy
• 出版年：2013
• 出版时间：May, 2013
• 年：2013
• 卷：108
• 期：Complete
• 页码：211-222
• 全文大小：1353 K

文摘

A new stilbazolium dye 4-{(E)-2-[4-(dimethylamino)naphthalen-1-yl]ethenyl}-1-methylquinolinium iodide monohydrate (DANSQI) having enlarged ¦Ð-conjugated system was synthesized and characterized by X-ray diffraction, IR, Raman, UV-Vis, Fluorescence, ¹H- and ¹³C NMR spectroscopy. Quantum chemical calculations were performed to obtain electronic structure and vibrational data, using DFT. The crystals are monoclinic, space group P2₁/n, with a = 8.0751(14), b = 25.839(4), c = 10.9031(15) ?, V = 2141.4(6) ?³, and Z = 4 (at 300(2) K). The unit cell contains four molecules of the dye, participating in weak intermolecular interactions. The cation is nearly flat with a deviation of the planarity of 5.08 (1)¡ã. The dye investigated is the first stilbazolium iodide containing water molecule in the solid state therefore the N-dimethylamino group declines significantly from planarity, as indicated by C13N1C2C3 torsion angle of 16.08¡ã. The dye studied shows solvatochromism of 84 nm in visible region and very large Stokes shift up to 253 nm. The intensity of fluorescence bands strongly depends on solvent polarity.