Trifluoroacetyl‐Substituted D–π–A Fluorophores: Design Strategies for Strong Solvatochromism and Giga Stokes Shifts

Chemistry - An Asian Journal, Journal Year: 2025, Volume and Issue: unknown

Published: April 30, 2025

Solvatochromic fluorophores, widely employed in various analytical applications such as environmentally responsive dyes, typically feature a donor-π-acceptor (D-π-A) structure. Most recently, Klymchenko and we independently designed D-π-A fluorophores with strong acceptor, trifluoroacetyl group, to achieve fluorescent solvatochromism reported its application membrane analysis (Klymchenko et al. Anal. Chem. 2024, 96, 13242) molecular thermometer (Konishi J. Am. Soc. 2025, 147, 9953), respectively. However, these reports have only considered few π-electron donors including dialkylamines. There is not enough scope for solvatochromic that take advantage of the properties group. In this study, systematically investigated π-conjugated aromatic skeleton groups. The relationship between dye structure absorption, fluorescence, quantum yield were clarified, design strategy exhibit desired was established. Moreover, fluorescence quenching can occur depending on solvent selection or study provides insightful trifluoroacetyl-based strategy, emphasizing their prospective but underused acceptor units next fluorophore development.

Language: Английский

Synthesis of Side-Chain Liquid Crystalline Polyacrylates with Bridged Stilbene Mesogens

Molecules, Journal Year: 2024, Volume and Issue: 29(21), P. 5220 - 5220

Published: Nov. 4, 2024

In recent years, π-conjugated liquid crystalline molecules with optoelectronic functionalities have garnered considerable attention, and integrating these into side-chain polymers (SCLCPs) holds potential for developing devices that are operational near room temperature. However, it is difficult to design SCLCPs excellent processability because mesogens rigid rods, low solubility in organic solvents, a high isotropization Recently, we developed near-room-temperature nematic crystals based on “bridged stilbene”. this work, synthesized polyacrylate SCLCP incorporating bridged stilbene exhibited phase temperature could maintain crystallinity more than three months. We conducted thorough structure analysis evaluated the optical properties. The birefringence values of resulting were higher those corresponding monomers enhanced order parameters due polymer effect. addition, inherited mesogen-derived AIE properties, quantum yields (Φfl = 0.14–0.35) solid state. It noteworthy maximum fluorescence wavelength redshift greater 27 nm as consequence film formation. Thus, several unique characteristics unattainable small molecular systems.

Language: Английский

Engineering “Meso‐Atom” Bonding: Honeycomb‐Network Transitions in Reticular Liquid Crystals

Aggregate, Journal Year: 2024, Volume and Issue: unknown

Published: Dec. 26, 2024

ABSTRACT A library of rod‐like bolapolyphiles with sticky hydrogen‐bonded glycerol groups at their ends and having highly branched side chains a carbosilane‐based four‐way branching point, all based on the same oligo(phenylene ethynylene) core, has been synthesized investigated. For these compounds, A15‐type Frank–Kasper phase is formed upon side‐chain elongation in steric frustration range transition from triangular to much larger square honeycombs. In contrast previously known tetrahedral sphere packings A15 this case by networks aggregates parallelly organized π‐conjugated rods. This allows design compounds wide ranges network down room temperature. However, its formation becomes strongly disfavored core fluorination that attributed changing mode core–core interaction also modifies honeycombs deformation squares into rectangular or rhombic cells, either without emergence tilt

Language: Английский