Electronic properties modulation of tetraoxidothieno[3,2-b]thiophene-based quinoidal compounds by terminal fluorination

Abstract

The electronic properties of IDOTT could be finely modulated via terminal fluorination.

Quinoidal Small Molecule Containing Ring-Extended Termini for Organic Field-Effect Transistors

“…Excitation from the ground state to the lower level is forbidden, but transition to a higher energy level is allowed, resulting in blue-shifted absorption. Similar H-aggregation tendency has been reported for isatin-terminated and other quinoidal molecules, which could be attributed to high planarity and rigidity of the molecular structure. , …”

“…Similar H-aggregation tendency has been reported for isatin-terminated and other quinoidal molecules, which could be attributed to high planarity and rigidity of the molecular structure. 22,39 CV measurements were carried out using a degassed CH 3 CN solution containing 0.1 M Bu 4 NPF 6 as a support electrolyte. BzTQuT showed a quasi-reversible reduction and two quasi-reversible oxidation waves, and QuT showed a quasireversible reduction and a quasi-reversible oxidation waves (Figure S4).…”

All-fused-ring small molecule acceptors with near-infrared absorption

“…Considering that the introduction of fluorine atoms on terminal groups affects the molecular charge distribution and molecular packing, we speculate that the low crystallinity of FM4 may be due to its suitable charge distribution and complex intermolecular interactions. 55,56 The NIR absorption, low-lying LUMO/HOMO energy levels and high electron mobility enable FM3 and FM4 to be used as n-type semiconductors in opto-electronic devices.…”

Significant alternation of molecular structures and properties in quinoidal conjugated polymers by chalcogen atom substitution

“…The cyclic voltammograms exhibited distinctive reduction peaks, which are commonly observed in isatinterminated thienoquinoid molecules or polymers. 18,19,42 In addition, they showed relatively weaker oxidation potentials than reduction potentials. Based on their reduction and oxidation onsets, the E LUMO and E HOMO were À5.17 and À3.58 eV for PmQEDOT-T2 and À5.17 and À3.70 eV for PmQEDTT-T2, respectively (Table 3).…”

“…Since the N-alkylated isatin-terminated thienoquinoid compounds were first reported in 1993, 15 diverse classes of indophenine derivatives have been developed for applications as molecular dyes and organic semiconductors. 7,16,17 Unlike the quinoidal molecules composed of dicyanomethylene (DCM) terminal groups, which are commonly used to build quinoid structures, isatin-based quinoidal building blocks have some advantages: the structures of terminated isatin and thiophene derivative cores can be conveniently modified 18 and the potential C-C coupling can facilitate polymerization. 19 Therefore, several quinoidal building blocks for conjugated polymers have been developed through facile synthetic procedures.…”