A naphthalimide-based fluorophore (HONIOH) was designed by introducing a hydroxy unit into the 4th position of the aromatic core and a hydroxypropyl unit into the N-imide site. Photophysical properties of HONIOH were highly dependent on solvents, which was ascribed to the excited state proton transfer (ESPT) coupled with intramolecular charge transfer (ICT) mechanism. Further studies demonstrated that HONIOH can be used to recognize N, N-dimethylformamide (DMF) qualitatively and differentiate methanol from ethanol. Three control compounds were synthesized, their photophysical properties were investigated in various solvents, and experimental results revealed that hydroxyl and hydroxypropyl units contribute to the solvents differentiation ability of HONIOH. In addition, HONIOH was successfully applied as a colorimetric, fluorescent probe for the discriminative detection of trace water in organic solvents, such as fluorescence turn-on response accompanied by fluorescent color changes from light yellow to purple in DMF, and fluorescence turn-off response and blue to yellow fluorescent color changes in acetonitrile, tetrahydrofuran, and acetone. We believe that N-substituted 4-hydroxynaphthalimide derivatives may find widespread applications in chemical and biochemical sensing and imaging.

通过将羟基单元引入芳族核的第4位并且将羟丙基单元引入N-酰亚胺位来设计基于萘二甲酰亚胺的荧光团（HONIOH）。HONIOH的光物理性质高度依赖于溶剂，这归因于激发态质子转移（ESPT）和分子内电荷转移（ICT）机理。进一步的研究表明，HONIOH可用于定性识别N，N-二甲基甲酰胺（DMF）并将甲醇与乙醇区分开。合成了三种控制化合物，在各种溶剂中研究了它们的光物理性质，实验结果表明羟基和羟丙基单元对HONIOH的溶剂分化能力有贡献。此外，HONIOH已成功应用于比色法，用于区分性检测有机溶剂中痕量水的荧光探针，例如在DMF中荧光开启响应伴随着荧光颜色从浅黄色变为紫色，乙腈，四氢呋喃中的荧光关闭响应以及蓝色到黄色荧光颜色变化和丙酮。我们相信，N-取代的4-羟基萘二甲酰亚胺衍生物可能会在化学和生化传感和成像中找到广泛的应用。