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In this contribution, a dye (C8-alkyl substituted Naphthalimide-Coumarin, CNC) with naphthalimide and coumarin incorporated together with -NHN = bridge unit. The compound was fully characterized by NMR and HRMS spectroscopic techniques. Highly emissive character was investigated in detail in various polar environments. The emission maximum varied from 430 to 470 nm. In polycarbonate film, CNC is also highly emissive with 560 nm emission peak. While in sold, the emission maximum was further shifted to 580 nm due to the more tightly packing mode than that in film. The C8-alkyl substitution enhances the solubility of CNC and also contributes most to its solid emission. [ABSTRACT FROM AUTHOR]

In this article, a dye with naphthalimide and coumarin was configured and was fully characterized. Its emission behavior was investigated in medium polar solvent. The emission behavior shows that there is no obvious energy transfer between naphthalimide and coumarin. Therefore, both the emission of naphthalimide and coumarin exhibit in the emission spectra, including blue and yellow part. The emission in film and solid shows different character. In film, single emission peak was observed. However, the solid emission covered a broad scope, including blue and yellow integrant. All the emission color was indicated by (Commission Internationale de L'Eclairage) CIE coordinates. The CIE coordinate of solid emission (0.29, 0.33) is approaching the ideal white light. [ABSTRACT FROM AUTHOR]

A propeller conformed triphenylamine molecule was decorated with naphthalimide. The two fluorophores were bonded with alkynyl bridge unit, which conjugates the two fragments. The resulting compound was fully characterized. Several solvents were used to investigate its absorption and emission behavior with the solvent polarity variation from weak to strong. The quantum yield increased with the increasing of solvent polarity. It is also highly emissive in film and in a solid with significant emission shift toward longer wavelength, reaching to 544 and 593 nm, respectively. The underlying signal mechanism was interpreted by the HOMO/LUMO potentials based on TDDFT calculations. [ABSTRACT FROM PUBLISHER]

Naphthalimide and coumarin were bonded together with –NHN= being as the linkage. The emission behavior was investigated in various solvents. The energy transfer is independent in weak and medium polarity solvents. Efficient energy transfer occurred with the emission of it in polar solvent. In addition, it is highly emissive in polycarbonate and the energy transfer from coumarin to naphthalimide is more efficient. Another significant feature is its selective F−response. Upon the F−addition, the absorption around 444 nm shifted to 486 nm. And the new absorption band decreased and another new absorption band appeared around 574 nm. [ABSTRACT FROM AUTHOR]

In this contribution, a sensitive colorimetric chemosensor was constructed based on the framework of naphthalimide. And it was characterized by NMR and mass spectroscopic techniques. The solution color changed from yellowish to deep blue with the addition of OH−. The obvious color change can be distinguished by naked eye. Excellent selectivity against other common anions was also observed. Even if the strong Lewis base F−added to the dye solution, no color change was induced. The effects imposed on the obvious color change can be ascribed to the deprotonation of –NH– of bridge unit. The results of structural optimization and molecular orbital calculation uncovered the underlying signal mechanism. Due to the depronotion effect, lowered energy gap (HOMO/LUMO) and electron redistribution leads to the red-shift of longest maximum absorption. [ABSTRACT FROM AUTHOR]

Two naphthalimide based chemosensors were synthesized. Upon the addition of OH−or F−, the solution color turned from pink to blue due to the proton elimination of N-H/O-H. The electron density increased on the nitrogen atom and enhanced the intramolecular charge transfer, which resulted in a red-shift of the absorption band. This color change was reversible with H+/MeOH addition and can be detected with the naked eye. The selectivity of the two dyes toward OH−/F−compared with other anions was investigated. The underlying signal mechanism was interpreted by the HOMO/LUMO potentials. Significantly lowered energy gap supported the red-shift absorption band. [ABSTRACT FROM PUBLISHER]

In this contribution, a new sensitive colorimetric chemosensors based naphthalimide was synthesized and characterized by NMR and mass spectroscopic techniques. Upon the addition of OH-, the solution of dye change its color from yellowish to deep blue, which can be easily observed by naked eye. The sensors show good selective against other common anions, including strong Lewis base F−. The effects of deprotonation/protonation imposed on absorption spectrum were investigated. Further quantum chemical calculation uncovered the underlying signal mechanism. The lowered energy gap between HOMO/LUMO in NB-H leads to the longest maximum absorption (665 nm). [ABSTRACT FROM AUTHOR]

Double build-in chromophores, naphthalimide (NIM) and bisindolymaleimide (BIM), were synthesized and characterized. Absorption and emission properties of double chromophores dye were fully investigated in various solvents. The priority of through bond energy transfer (TBET) toNTMorBIMis solvent dependent. There appears large different emission wavelength change in CHCl3and DMF with alkyl attached toBIM. However, the product of cyclohexyl substitution leads to a different emission behavior, which is non-sensitivity to solvent polarity. Quantum chemical calculation for the molecular orbital reveals that intramolecular charge transfer (ICT) is the key factor for their different opto-electronic properties. [ABSTRACT FROM PUBLISHER]