A Molecular Design towards a Highly Amphoteric and Polar Molecule (HAPM) to Assemble Novel Organic Solid-State Structures

• Published in: Molecular crystals and liquid crystals science and technology. Section A, Molecular crystals and liquid crystals Vol. 333; no. 1; pp. 243 - 258
• Main Authors: Sato, Naoki, Kawamoto, Ikuko, Sakuma, Taro, Silinsh, Edgar A., Jurgis, Andrejs J.
• Format: Journal Article
• Language: English
• Published: Philadelphia, PA Taylor & Francis Group 01.08.1999; Gordon and Breach
• Subjects: amphoteric molecule; Atomic and molecular physics; Calculations and mathematical techniques in atomic and molecular physics (excluding electron correlation calculations); Chemistry; dipole moment; Electronic structure of atoms, molecules and their ions: theory; Exact sciences and technology; Heterocyclic compounds; Heterocyclic compounds with o, s, se, te hetero atom and condensed derivatives; intermolecular charge transfer; intramolecular charge transfer; molecular packing; Organic chemistry; Physics; Preparations and properties; Semi-empirical and empirical calculations (differential overlap, hückel, ppp methods, etc.); Statistical model calculations (including Thomas-Fermi and Thomas-Fermi-Dirac models); Amphoteric; Molecular packing; Nitrile; Electron affinity; Electron charge distribution; Sulfur heterocycle; Electrochemical properties; Molecular assembly; Bicyclic compound; Ionization potential; Quinonemethide; Electronic transition; Charge transfer; Dipole moment; Polar molecule
• ISSN: 1058-725X
• DOI: 10.1080/10587259908026008

To approach a novel molecular assembly with notable electronic properties, a molecular design towards highly amphoteric and polar molecules (HAPMs) as its building blocks is proposed. This design stresses the combination of two different π-molecular segments, electron-donating and accepting ones, particularly with a pseudo-delocalized π-election system. To examine the suggested contrivance, 2-(4-dicyanomethylenecyclohexa-2,5-dienylidene)-4,5-ethylenedithio-1,3-dithiole 1 was designed and synthesized as a test molecule. Semiempirical MO calculations of 1 and its extended quinonoid analogues indicate a moderately strong intramolecular charge-transfer working in the molecules in the ground state. Moreover, several experimental results of 1, e.g., its absorption spectra and cyclic voltammograms, imply that most characteristics expected for HAPM are in principle recognized in 1, though further improvements needed to clear the whole requirements for it.