Charge-transfer interaction of aspartame and neotame with several π-acceptors: Stoichiometric data.
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ABSTRACT:
SUBMITTER: Adam AMA
PROVIDER: S-EPMC8120938 | biostudies-literature |
REPOSITORIES: biostudies-literature
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Project description:This article is related to a research paper entitled "Exploring the charge-transfer chemistry of fluorine-containing pyrazolin-5-ones: The complexation of 1-methyl-3-trifluoromethyl-2-pyrazoline-5-one with five π-acceptors" [J. Mol. Liq. 331 (2021) 115814] [1]. Herein we present photographic data that showed the color change after mixing methanolic solutions of 1-methyl-3-trifluoromethyl-2-pyrazoline-5-one (donor) with each of the investigated π-acceptor [picric acid (PA), chloranilic acid (CLA), fluoranil (TFQ), DDQ, and TCNQ]. Stoichiometry data for the interaction of the donor with all acceptors determined in solution state by the spectrophotometric titration method and the Job's continuous variation method were presented. The data presented are useful for understand that the charge-transfer (CT) complexation between a donor and an acceptor, generally, is characterized by a strong color change, and to understand the stoichiometry between these molecules.
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Project description:A new family of liquid π-donors, lipophilic dihydrophenazine (DHP) derivatives, show remarkably high π-electron-donor property which exhibit supramolecular alternating copolymerization with 7,7,8,8-tetracyanoquinodimethane (TCNQ), giving ionic charge-transfer (ICT) complexes. The ICT complexes form distinct columnar liquid crystalline (LC) mesophases with well-defined alternating molecular alignment as demonstrated by UV-Vis-NIR spectra, IR spectra, and X-ray diffraction (XRD) patterns. These liquid crystalline ICT complexes display unique phase transitions in response to mechanical stress: the columnar ICT phase is converted to macroscopically oriented smectic-like mesophases upon applying shear force. Although there exist reports on the formation of ICT in the crystalline state, this study provides the first rational identification of ICT mesophases based on the spectroscopic and structural data. The liquid crystalline ICT phases are generated by strong electronic interactions between the liquid π-donors and solid acceptors. It clearly shows the significance of simultaneous fulfillment of strong π-donating ability and ordered self-assembly of the stable ICT pairs. The flexible, stimuli-responsive structural transformation of the ICT complexes offer a new perspective for designing processable CT systems with controlled hierarchical self-assembly and electronic structures.
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