Axially chiral 1,4-dihydropyridine derivatives: aggregation-induced emission in exciplexes and application as viscosity probes

Yang, Zeren; Huo, Yanmin; Liu, Yanke; Du, Guifen; Zhang, Wenhao; Zhou, Ling; Zhan, Lihui; Ren, Xuerui; Duan, Wenzeng; Gong, Shuwen

doi:10.1039/c9ra06553a

Cited by 6 publications

(2 citation statements)

References 34 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The 4-methylene-1,4-dihydropyridine ( DHP ) scaffold has been utilized in the design of fluorophores, which include AIE-active/solid-emissive molecules. − This simple scaffold permits the fine-tuning of their photophysical properties through substituents on its periphery. For instance, the introduction of electron-withdrawing substituents at the C-4 position and electron-donating substituents at the C-2 and C-6 positions resulted in push–pull type dyes. , Apart from the electronic tuning at these locations, substituents on the DHP nitrogen can influence the molecular packing in the solid state, which is known to contribute to the solid-state emission …”

Section: Introductionmentioning

confidence: 99%

Substituent-Controlled Photophysical Responses in Dihydropyridine Derivatives and Their Application in the Detection of Volatile Organic Contaminants

Kanneth,

Mathew,

Parameswaran

et al. 2023

J. Org. Chem.

View full text Add to dashboard Cite

In the ever-expanding realm of organic fluorophores, structurally simple and synthetically straightforward molecules with unique photophysical properties have received special attention. Among these, 1,4-dihydropyridine (DHP) is an important scaffold that permits fine-tuning of their photophysical properties through substituents on the periphery. Herein, we describe a series of solid-emissive N-substituted 2,6-dimethyl-4-methylene-1,4-dihydropyridine derivatives appended with electron-withdrawing substituents (dicyanomethylene or 2-dicyanomethylene-3-cyano-2,5-dihydrofuran) at the C-4 position and alkyl or alkylaryl groups on the DHP nitrogen. Electronic and steric tuning exerted by these substituents resulted in interesting photophysical properties such as negative solvatochromism, solidstate, and aggregation-induced emission (AIE). Theoretical calculations were carried out to explain the solvatochromic properties. Insight into the AIE properties was obtained through variable-temperature nuclear magnetic resonance and viscosity- and temperature-dependent emission studies. The variations in molecular packing in the crystal lattice with changes in the N-substituents contributed to the tuning of solid state emission properties. Detection of aromatic volatile organic compounds (VOCs) was achieved using the aggregates of the DHP derivatives. Among the VOCs, p-xylene elicited a significant enhancement in emission, allowing its detection at submicromolar levels.

show abstract

Section: Introductionmentioning

confidence: 99%

Substituent-Controlled Photophysical Responses in Dihydropyridine Derivatives and Their Application in the Detection of Volatile Organic Contaminants

Kanneth,

Mathew,

Parameswaran

et al. 2023

J. Org. Chem.

View full text Add to dashboard Cite

show abstract

“…This aspect allows versatile methodological designs that cannot be accomplished using normal fluorophores. For example, optical sensors have been developed to measure temperature, , pH, , and viscosity , based on the unique nature of AIEs. AIE-based sensors have many advantages, such as the facile structural modification of AIEgens, high molecular stability, and high sensitivity. ,, Zhao et al developed pH- and temperature-sensitive hydrogel nanoparticles with TPE derivative doped into the shells .…”

Section: Introductionmentioning

confidence: 99%

Space Size-Dependent Transformation of Tetraphenylethylene Carboxylate Aggregates by Ice Confinement

et al. 2020

View full text Add to dashboard Cite

Tetraphenylethylene carboxylate (TPEC) aggregates are transformed by ice confinement, which is controlled by the initial concentration of sucrose employed as a cryoprotectant and temperature. The freezing of aqueous sucrose leads to the formation of micro- or nanoliquid phase confined in ice. Aggregation-induced emission (AIE) of tetraphenylethylene carboxylate (TPEC) in the ice-confined space is explored using fluorescence spectroscopy and lifetime measurements. The characteristics of AIE in the ice-confined space strongly depend on the initial sucrose concentration and temperature, which determine the size of the liquid phase. The AIE of TPEC in the ice-confined space can be classified into three regimes in terms of spectroscopic features. Loosely packed J aggregates of TPEC are formed in the microliquid phase (>2 μm). The fluorescence intensity increases, and the wavelength is hypsochromically shifted with a decrease in the size of the space, indicating that the molecular arrangement in the aggregate depends on the space size. The fluorescence lifetimes indicate polydisperse, loosely packed aggregation. No further change in aggregate structure is observed once the liquid phase size is decreased to ∼2 μm, and a spectroscopically identical structure is maintained upon further reduction of the space size to ∼0.5 μm. The molecular arrangement in the aggregate is independent of the space size in this regime. However, when the size of the space becomes smaller than ∼0.5 μm, the aggregate structure again starts to change into a more tightly packed aggregate and a hypsochromic shift of the fluorescence wavelength occurs again. The fluorescence lifetime indicates monodispersed aggregation in this submicrospace.

show abstract

Recent trends in molecular aggregates: An exploration of biomedicine

et al. 2022

View full text Add to dashboard Cite

Molecular aggregates are receiving tremendous attention, demonstrating immense potential for biomedical applications in vitro and in vivo. For instance, the molecular aggregates of conventional fluorophores influence the electronic excitation states of the aggregates, causing characteristic photophysical property changes. A fundamental understanding of this classical relationship between molecular aggregate structures and photophysics has allowed for innovative biological applications. The chemical characteristics of drug molecules generally trigger the formation of colloidal aggregates, and this is considered detrimental to the drug discovery process. Furthermore, nano-sized supramolecular aggregates have been used in biomedical imaging and therapy owing to their optimal properties for in vivo utility, including enhanced cell permeability, passive tumor targeting, and convenient surface engineering. Herein, we provide an overview of the recent trends in molecular aggregates for biomedical applications. The changes in photophysical properties of conventional fluorophores and their biological applications are discussed, followed by the effects of conventional drug molecule-aggregates on drug discovery and therapeutics development. Recent trends in the investigation of biologically important analytes with aggregation-induced emission are discussed for conventional and unconventional fluorophores. Lastly, we discuss nano-sized supramolecular aggregates used in imaging and therapeutic purposes, with a focus on in vivo utilization.

show abstract

Axially chiral 1,4-dihydropyridine derivatives: aggregation-induced emission in exciplexes and application as viscosity probes

Abstract: Axially chiral 1,4-dihydropyridine derivatives ((R)-/(S)-2) with aggregation-induced emission (AIE) in exciplex were designed and synthesized. They have excellent CD signals and can determine the different viscosity in mixed solvents.

Cited by 6 publications

References 34 publications

Substituent-Controlled Photophysical Responses in Dihydropyridine Derivatives and Their Application in the Detection of Volatile Organic Contaminants

Substituent-Controlled Photophysical Responses in Dihydropyridine Derivatives and Their Application in the Detection of Volatile Organic Contaminants

Space Size-Dependent Transformation of Tetraphenylethylene Carboxylate Aggregates by Ice Confinement

Recent trends in molecular aggregates: An exploration of biomedicine

Contact Info

Product

Resources

About