Mechanofluorochromic properties of fluorescent molecules based on a dicyanomethylene-4H-pyran and indole isomer containing different alkyl chains via an alkene module

Abstract

The length and isomerization of the alkyl chains exhibit different effects on the mechanofluorochromic properties of the dicyanomethylene-4H-pyran derivatives when the substitution position of the indole unit is different.

Polymorphism and Multicolor Mechanofluorochromism of a D-π-A Asymmetric 4H-Pyran Derivative with Aggregation-Induced Emission Property

“…4 H -Pyran derivatives are a class of D-π-A fluorescent compounds where various electron acceptors and electron donors were easily introduced into the parent unit by simple chemical reactions, which are widely used in the fields of fluorescent sensors, organic electroluminescent diodes, molecular logic gates, etc. − Recently, some 4 H -pyran derivatives have been reported to exhibit polymorphic, AIE, and/or solid-state fluorescence stimulus response properties. − Very recently, some asymmetric 4 H -pyran derivatives were reported to exhibit higher contrast MFC activities than the corresponding symmetric compounds because the low symmetry was conducive to obtaining crystalline structures, which were easily destroyed by external forces . Although several 4 H -pyran derivatives were reported to simultaneously exhibit AIE, polymorphic, and MFC characteristics, as far as we know, these kinds of 4 H -pyran derivatives with multiple crystalline polymorphs have not been reported.…”

Synthesis of indole-based chromophores with TCF acceptor and the study of the quinoxalinone core effect on the linear and nonlinear optical properties

“…Indole-based chromophore with short vinylene π-bridge Ind-V-TCF has been synthesized via a two-step procedure starting from indole-3-carboxaldehyde: alkylation by dodecylbromide with the formation of Ndodecyl derivative 2 32 and following Knoevenagel condensation with 3-cyano-2-dicyanomethylene-4,4,5trimethyl-2,5-dihydrofurane (Me-TCF) 33 (Scheme 1). The long-chain dodecyl substituent was used to increase the chromophore solubility in organic solvents.…”

Tunable mechanochromic luminescence of benzofuran-fused pyrazine: effects of alkyl chain length and branching pattern

“…There are additional examples of side chain engineering for controlling on/off switching of MCL or the self-recovery rate. 36–50…”

“…There are additional examples of side chain engineering for controlling on/off switching of MCL or the self-recovery rate. [36][37][38][39][40][41][42][43][44][45][46][47][48][49][50] Recently, we have synthesized several bis(benzofuro)[2,3-b:2 0 ,3 0e]pyrazine (BBFPz) derivatives (Fig. 1, Linear-R).…”