Hariharan, Palamarneri Sivaraman; Pan, Chengjun; Karthikeyan, Subramanian; Xie, Dexun; Shinohara, Akira; Yang, Chuluo; Wang, Lei; Anthony, Savarimuthu Philip published the artcile< Solvent vapour induced rare single-crystal-to-single-crystal transformation of stimuli-responsive fluorophore: Solid state fluorescence tuning, switching and role of molecular conformation and substituents>, Name: 2-(3,4-Difluorophenyl)acetonitrile, the main research area is solvent vapor crystal transformation fluorescence tuning switching conformation polymorph.
The substituent groups in the aggregation-induced-emissive (AIE) tetraphenylethylene (TPE) based donor (D)-acceptor (A) fluorophores (TPPA-1-6) were tailored. and fluorescent polymorphs formation and single-crystal-to-single-crystal (SC-SC) transition in the solid state was explored. TPPA-1 showed conformational fluorescent polymorphs via twisted and coplanar conformation between TPE Ph group and cyanophenyl acceptor Ph ring. However, single crystal anal. of other derivatives revealed that substituent groups and supramol. interactions control the mol. conformation and SC-SC transition. Fluorophore with same substituent but positional change also show drastic effect on the fluorescent polymorphs formation and SC-SC transition. Substituents that can form strong intermol. interactions stabilize the less stable coplanar structure whereas bulky substituents with weak intermol. interactions produced twisted or both conformers. Photophys., powder x-ray diffraction (PXRD), DSC and thermogravimteric (TG) anal. were performed to substantiate and get insight on the structural transformation. The formation of fluorescent polymorphs and SC-SC transition exhibited tunable and switchable solid state fluorescence. The nonplanar TPE core was made use to demonstrate high contrast stimuli induced reversible fluorescence switching. Overall, the present studies attempted to gain information on the structural design for developing SC-SC transforming functional organic fluorescent materials that could be of potential interests for optoelectronic and display devices.
Dyes and Pigments published new progress about Conformational transition. 658-99-1 belongs to class nitriles-buliding-blocks, and the molecular formula is C8H5F2N, Name: 2-(3,4-Difluorophenyl)acetonitrile.
Referemce:
Nitrile – Wikipedia,
Nitriles – Chemistry LibreTexts