Synthesis and photophysical properties of extended π conjugated naphthalimides

Abstract

A series of π conjugated naphthalimide derivatives having an imide group as an acceptor conjugated with a methoxy arylethynyl or a methoxyphenyl triazole as a donor were prepared by Sonogashira coupling or "click" chemistry. Their photophysical properties were investigated by steady state and time resolved fluorescence spectroscopy and modelled by TD-DFT calculations. Compound Naphth-AlkyneOMe has a high fluorescence quantum yield and displays efficient photoinduced charge transfer in solution as well as in the powder state. Compound Naphth-TriazoleOMe exhibits a very high Stokes shift and its fluorescence quantum yield is low, which can be rationalized by theoretical calculations.

Quinoidization of π‐Expanded Aromatic Diimides: Photophysics, Aromaticity, and Stability of the Novel Quinoidal Acenes

“…addition reaction of π-acidic diimides in the presence of phosphine disulfide, as Lawesson's reagent, to afford QDM 1. Inspired by the earlier success to convert readily available naphthalene diimides to the corresponding triplet sensitizer by modulating the intrinsic aromaticity of the π-core, we wish to extend the new cycloaddition reaction to other π-expanded acene diimides [15][16][17][18] to afford novel quinoidal acene triplet sensitizers quinoidal benzotetraphene 2 and its thiophene analog 3 (Figure 1). Unexpectedly, quinoidal thiophene 3 decomposes during purification.…”

Fluorescent Imprinted Nanoparticles for Sensing of Chlorogenic Acid in Coffee Extracts

“…tron transfer) communication between the receptor and the fluorophore n modinamically favored, and it becomes cut off, since the lone pair of electrons o ceptor are no longer available after recognition of the analyte. As it has been rep the literature, in these types of "off-on" systems, that protons from the analyte ele ically attract the electrons, thus increasing the oxidation potential of the analyt receptor [33,34]. solvent from DMSO a (at a pH o bathochromic shift with respect to the system observed, the e maxima registered at 540 nm instead of 530 nm.…”

“…In Figure 8, we can observe a three-fold increase in fluorescent intensity at the emission maximum of 530 nm by addition of the analyte. The fluorescence enhancement is probably due to the hydrogen transfer between the carboxilic group of the analyte and the amino group of the monomer 7 present in fMIP01, making PET (photoinduced electron transfer) communication between the receptor and the fluorophore not thermodinamically favored, and it becomes cut off, since the lone pair of electrons of the are longer available of the As it has been reported in the literature, in these types of "off-on" systems, that protons from the analyte electrostatically attract the electrons, thus increasing the oxidation potential of the analyte-bound receptor [33,34].…”

Naphthalimide Assemblies for Simultaneous Detection of Ferrous Ion and H2O2 to Prevent Fenton Reaction

“…Keeping this in view, we planned to design and synthesize naphthalimide based compound Naph‐MDHP having morpholine and dihydropyridine moieties appended with it. We chose the naphthalimide scaffold due to its AIE characteristics and good photophysical properties [21,22] . Morpholine is known for its binding affinity towards iron [23,24] and dihydropyridine moiety known for its binding toward reactive oxygen species [25,26] …”