Synthesis, Photophysical Properties and Self-Assembly of a Tetraphenylethylene-Naphthalene Diimide Donor-Acceptor Molecule.

The development of new π-conjugated molecular structures with controlled self-assembly and distinct photophysical properties is crucial for advancing applications in optoelectronics and biomaterials. This study introduces the synthesis and detailed self-assembly analysis of tetraphenylethylene (TPE) functionalized naphthalene diimide (NDI), a novel donor-acceptor molecular structure referred to as TPE-NDI. The investigation specifically focuses on elucidating the self-assembly behavior of TPE-NDI in mixed solvents of varying polarities, namely chloroform: methylcyclohexane (CHCl3 : MCH) and chloroform: methanol (CHCl3 : MeOH). Employing a several analytical methodologies, including UV-Vis absorption and fluorescence emission spectroscopy, scanning electron microscopy (SEM), X-ray diffraction (XRD), and dynamic light scattering (DLS), these self-assembled systems have been comprehensively examined. The results reveal that TPE-NDI manifests as distinct particles in CHCl3 : MCH (fMCH =90 %), while transitioning to flower-like assemblies in CHCl3 : MeOH (fMeOH =90 %). This finding underscores the critical role of solvent polarity in dictating the morphological characteristics of TPE-NDI self-assembled aggregates. Furthermore, the study proposes a molecular packing mechanism, based on SEM data, offering significant insights into the design and development of functional supramolecular systems. Such advancements in understanding the molecular self-assembly new π-conjugated molecular structures are anticipated to pave the way for novel applications in material science and nanotechnology.

Molecular nanoarchitectonics of proton triggered tetraphenylethylene-based detector: colorimetric, reversible, and intracellular pH.

In this paper, we designed, synthesized, and characterized 4,4',4'',4'''-(ethene-1,1,2,2-tetrayl)tetrakis(N,N-dimethylaniline) (1). Furthermore, UV-Vis absorbance and fluorescence emission studies reveal that 1 acts as a selective and sensitive probe for reversible acid-base sensing in solution as well as in the solid state. Nevertheless, the probe exhibited colorimetric sensing and intracellular fluorescent cell imaging of acid-base sensitive cells, making it a practical sensor with several potential applications in chemistry.

2H-Pyran-2-one-Functionalized Diketopyrrolopyrrole Dye: Design, Synthesis, and Explosives Sensor.

In this work, a 2H-pyran-2-one-functionalized diketopyrrolopyrrole (DPP) (coded as receptor 1) was designed, synthesized, and fully characterized by various spectroscopic methods. The physical properties of molecular architecture 1 were studied employing theoretical calculations. Receptor 1 was elegantly scrutinized for the sensing of explosive nitroaromatic compounds (NACs). Receptor 1 exhibited detection of nitro explosives, i.e., picric acid (PA), 2,4-dinitrophenol (DNP), and nitrophenol (NP), via the fluorescence quenching mechanism. The Stern-Volmer equation was employed to evaluate the effectiveness of the quenching process. It was found that 1 exhibited a detection limit of about 7.58 × 10-5, 8.35 × 10-5, and 9.05 × 10-5 M toward PA, DNP, and NP, respectively. The influence of interfering metal ions and anions on PA detection was investigated thoroughly. Furthermore, receptor 1-based low-cost fluorescent thin-layer chromatography (TLC) plates were developed for the recognition of PA.

Direct Arylation: A Greener Synthesis of Anthraquinone-Naphthalene diimide-Based Small Chromophores for Applications in Organic Thin Film Transistors.

In this paper, we report the design and synthesis of three naphthalene diimide- (NDI) and anthraquinone- (AQ) based organic chromophores derived from direct arylation reactions; NDI-AQ, AQ-NDI-AQ and NDI-AQ-NDI. Compared to classic cross-coupling reactions, this method reduced the number of synthetic and purification steps. The chemical structures, photophysical and electrochemical properties of these molecules were characterized using UV-vis spectroscopy, fluorescence emission spectroscopy and cyclic voltammetry (CV). The optoelectronic properties of the three dyes enabled the fabrication of organic thin film transistors (OTFTs). The fabricated OTFTs displayed good n-type semiconducting properties, with electron mobilities ( µ e ${{\mu }_{e}}$ ) of 1.5-4.2×10-4  cm2  V-1 s-1 .