El-Sayed Mohamed, Spange Stefan
General Organization of Export and Import Control, Food Testing Laboratories, Customs Gate Number 20, Port-Said, Egypt.
J Phys Chem B. 2007 Jun 28;111(25):7224-33. doi: 10.1021/jp070024t. Epub 2007 Jun 6.
Solvatochromism of the long wavelength band in the electronic absorption spectra of N-(4-nitrophenyl)-L-proline, NLP, N-(4-nitrophenyl)-D-proline, NDP, and N-(4-nitro-phenyl)-trans-4-hydroxy-L-proline, NHP, was studied and quantitatively described with Kamlet-Taft solvent polarity parameters. To evaluate the environmental effects for NLP, NDP, and NHP, the UV-vis spectroscopic behavior of these compounds was also investigated as pure crystals, as a guest in 2,6-O-dimethyl-beta-cyclodextrin, and also when adsorbed on Aerosil 300 silica particles from nonhydrogen-bond accepting solvents. Excellent Kamlet-Taft solvatochromic correlations were established for the three compounds in most solvents. Multiparameter correlations show the existence of specific solute-solvent interactions. A strong positive solvatochromic behavior was found for these compounds, indicating that their dipole moments were higher in the excited singlet state than in the ground state.
研究了N-（4-硝基苯基）-L-脯氨酸（NLP）、N-（4-硝基苯基）-D-脯氨酸（NDP）和N-（4-硝基苯基）-反式-4-羟基-L-脯氨酸（NHP）电子吸收光谱中长波长带的溶剂化显色现象，并用Kamlet-Taft溶剂极性参数进行了定量描述。为了评估NLP、NDP和NHP的环境效应，还研究了这些化合物作为纯晶体、作为2,6-O-二甲基-β-环糊精中的客体以及从非氢键接受溶剂吸附在Aerosil 300二氧化硅颗粒上时的紫外-可见光谱行为。在大多数溶剂中，这三种化合物都建立了良好的Kamlet-Taft溶剂化显色相关性。多参数相关性表明存在特定的溶质-溶剂相互作用。发现这些化合物具有很强的正溶剂化显色行为，表明它们在激发单重态的偶极矩高于基态。
