Synthesis of PPV-Based Conjugated Oligomer Containing Tropone in Main Chain

Abstract

The synthesis of a tropone-containing PPV-based conjugated oligomer by the Wittig polycondensation was investigated, where the tropone unit was introduced as the conjugated segment. Although the NMR and IR studies revealed the low molecular weight of the resulting product, no side reaction toward the carbonyl group in the tropone ring occurred to maintain the tropone structure as evidenced by the MALDI(Matrix-Assisted Laser Desorption Ionization)-TOFMS spectrum. The UV–vis and PL spectra gave preliminary information on the optical property of the tropone-containing conjugated oligomer.

Poly(cyclopropenone)s: Formal Inclusion of the Smallest Hückel Aromatic into π-Conjugated Polymers

“…The stability gained from this means that the charge does not delocalize as readily (via quinoidal electronic structures) and hence the observed reduction in conductivity is due to either decreased numbers or mobilities of extended charge carriers. This type of behavior was also observed for fused polycyclic tropone-containing polymers that were previously synthesized by Swager . There is a rich reactivity associated with these polymers, and we plan to study their spin properties in the presence of strong acids and alkylating agents in order to better understand the origins of these effects and to determine the extent of participation of formal cyclopropenium cations versus other electronic alterations.…”

“…The larger dipole moment of diphenylcyclopropenone (5.14 D) relative to benzophenone (3.0 D) would suggest enhanced basicity of the oxygen making up this highly polarized carbonyl bond . This work is very much complementary to other contemporary efforts to explore carbonyl-containing cyclopentadienone (4 π-electron) , and tropone (6 π-electron) , units within conjugated polymer backbones. Similar to the tropone case, we expected that formal protonation of the cyclopropenone (presumably at the carbonyl oxygen) would lead to a resonance contributor with more aromatic character along the backbone of the conjugated polymer (Scheme ).…”

Prospecting in Hückel‐space: From Hinokitiol to Non‐benzenoid Organic Electronics

“…Seminal studies by William Doering and by Hyp Dauben later led to the syntheses of tropone published back‐to‐back in a February 1951 issue of JACS , and synthetic contributions from Nozoe's group and others starting in the 1950s helped provide new routes to diverse tropone subunits . There are a few reports of tropone‐ and tropolone‐based conjugated polymer materials from the labs of Koji Takagi and Timothy Swager . Takagi's studies explored the electronic absorption properties of a variety of chemically synthesized copolymers spanning phenylene, phenylene vinylene, and fluorene comonomers ( e.g.…”

Tropone‐containing π‐conjugated polymers: Annulation of tropone onto benzene ring in the conjugated polymer

“…1). 34, 35 The introduction of the benzotropone unit into the PPV skeleton brought about the hypsochromic shift of the absorption spectrum and the decrease of the fluorescence intensity. Recently, we found that the absorption spectrum of P1 could be quasi‐reversibly changed by the addition of trifluoroacetic acid and triethylamine, which reflect the feature of low‐molecular‐weight tropone, although the detailed accounts for this phenomenon have not been obtained 36.…”