Thermo-Solvatochromism of Merocyanine Polarity Probes – What Are the Consequences of Increasing Probe Lipophilicity through Annelation?
作者:Clarissa T. Martins、Michelle S. Lima、Erick L. Bastos、Omar A. El Seoud
DOI:10.1002/ejoc.200700805
日期:2008.3
solvatochromism) of the three probes was studied in mixtures of water with propanol and/or with DMSO. The solvation model used explicitly considers the presence of three “species” in the system: bulk solution and probe solvation shell [namely, water (W), organic solvent (Solv)], and solvent–water hydrogen-bonded aggregate (Solv-W). For aqueous propanol, the probe is efficiently solvated by Solv-W; the strong
标题中提出的问题已通过比较两个系列极性探针的溶剂化显色性得到回答,通过增加连接到固定吡啶基结构的烷基 (R) 的长度或通过退火来增加其亲脂性(即,通过将苯环融合到基于吡啶的中心结构上)。合成了以下新型溶剂致变色探针:2,6-dibromo-4-[(E)-2-(1-methylquinolinium-4-yl)ethenyl]phenolate (MeQMBr2) 和 2,6-dibromo-4-[(E) )-2-(1-甲基吖啶鎓-4-基)乙烯基)]苯酚盐(MeAMBr2)。这些探针以及 2,6-dibromo-4-[(E)-2-(1-methylpyridinium-4-yl)ethenyl]phenolate (MePMBr2) 的溶剂化变色行为在增加探针亲脂性方面进行了分析,通过退火。以 kcal mol–1 为单位的经验溶剂极性标度 [ET(MePMBr2)] 的值与 ET(30) 线性相关,即广泛使用的探针