Construction of Donor–Acceptor Chromophores in Platinum Polyyne Polymer by [2 + 2] Cycloaddition of Organic Acceptors

Abstract

A thiophene-containing platinum polyyne polymer was postfunctionalized by a [2 + 2] cycloaddition followed by a cycloreversion of tetracyanoethylene (TCNE) or 7,7,8,8-tetracyanoquinodimethane (TCNQ), yielding narrow band gap polymers. The quantitative addition of the acceptor molecules was confi rmed by combined analytical techniques. The postfunctionalized platinum polyyne polymers displayed charge-transfer (CT) bands in the visible-near IR region and potent redox activities. The TCNQ adduct has a stronger electron-accepting feature than the TCNE adduct, as revealed by the more bathochromically shifted CT band and the lower fi rst reduction potential. The systematic investigation revealed a clear correlation between the optical and electrochemical band gaps.

Attempted Inversion of Semiconducting Features of Platinum Polyyne Polymers: A New Approach for All‐Polymer Solar Cells

“…This was due to the interactions between the cyano‐based acceptor moieties and polystyrene gels used in the GPC column. A similar GPC behavior was previously reported for aromatic polyamines and thiophene‐based platinum(II) polyyne polymers 10c, 12. The 1 H NMR and IR spectra of P4 and P5 suggested the reaction progress.…”

“…According to the previous method for reducing the polymer energy levels,12 the platinum(II) polyyne polymers were functionalized by the formal [2 + 2] cycloaddition‐retro‐electrocyclization reaction with TCNE. Due to the similarity to P2 as well as the limited solubilities, P3 was not subjected to this experiment (vide supra).…”

“…These energy level changes were supported by the thin film transistor performances 11. Recently, we also reported that the alkyne moieties of platinum(II) polyyne polymers can be functionalized by these reactions 12. It should be noted that the reactivity of TCNE to small‐molecular‐weight platinum(II) acetylides was comprehensively studied 13.…”

“…However, there has been no systematic investigation on the acceptor addition to platinum(II) polyyne polymers except for the proceeding paper from a domestic conference 14. Our recent study demonstrated that the TCNE addition to thiophene‐containing platinum(II) polyyne polymers lowers the LUMO level by approximately 1.5 eV, estimated from the onset reduction potentials 12. Thus, it is reasonable to apply this methodology of reducing polymer energy levels for the creation of novel n‐type materials.…”

Die [2+2]‐Cycloadditions‐Retroelektrocyclisierungs(CA‐RE)‐Klick‐Reaktion: ein einfacher Zugang zu molekularen und polymeren Push‐pull‐Chromophoren

“…im Tagungsbericht einer inländischen Konferenz erwähnt . Auf diesem Erfolg aufbauend synthetisierten Yuan und Michinobu das Polyin‐Polymer P24 vom Donor‐Akzeptor‐Typ . Die Substitution sowohl mit Thiophen‐ als auch mit Platin(II)‐Donoren erhöhte wirksam die Reaktivität der Hauptketten‐Alkine, und so wurde P24 unter mildem Erwärmen auf 70 °C erhalten.…”