High-yield and sustainable synthesis of quinoidal compounds assisted by keto–enol tautomerism

Abstract

The classical synthesis of quinoids, which involves Takahashi coupling and subsequent oxidation, often gives only low to medium yields. Herein, we disclose keto-enol-tautomerism-assisted spontaneous air oxidation of the coupling products...

n-Type Conjugated Polymers Based on an Indandione-Terminated Quinoidal Building Block

“…Very recently, we developed a new quinoidal system with indandione as the termini, which showed a deep E LUMO below −4.0 eV and pure n-channel behavior with an electron mobility (μ e ) up to 0.38 cm 2 V –1 s –1 . Both of these values are comparable to those of dicyanomethylene-terminated counterparts. , Importantly, bromine (Br) atoms can be introduced on the terminal phenyl rings, making these new quinoids promising A units for constructing CPs with low-lying E LUMO s by palladium-catalyzed polycondensation. Herein, we report two CPs, designated PIQ-A and PIQ-O, based on an indandione-terminated quinoidal A unit (Scheme ).…”

“…Both of these values are comparable to those of dicyanomethylene-terminated counterparts. 48,49 Importantly, bromine (Br) atoms can be introduced on the terminal phenyl rings, making these new quinoids promising A units for constructing CPs with low-lying E LUMO s by palladium-catalyzed polycondensation. Herein, we report two CPs, designated PIQ-A and PIQ-O, based on an indandione-terminated quinoidal A unit (Scheme 1).…”

A para-azaquinodimethane integrated quinoidal conjugated microporous polymer

“…It improves p-delocalization in the conjugated backbone significantly, bestowing interesting properties such as narrow band gaps, low lowest unoccupied molecular orbital (LUMO) energy and long-wavelength light absorption characteristics, among others. 6,[8][9][10] The special properties of these compounds has prompted the active development of several quinoidal-based small molecules [11][12][13] and one-dimensional polymers 9,14,15 for optoelectronic applications such as field-effect transistors, organic photovoltaics, photodetectors and photofilters etc. [16][17][18][19] Furthermore, quinoidal p-conjugated systems with large p-systems or D-A units exhibit biradical character (open shell), which may have applications in spintronics 20 and photonics, among others.…”

An extended quinoid molecule based on bis(thiophene-diketopyrrolopyrrole) with balanced ambipolar semiconducting properties and strong near-infrared absorption

“…In fact, many quinoid molecules were found to show promising semiconducting properties, mostly as n-type organic semiconductors. 15,[20][21][22][23][24][25][26][27][28][29] Diketopyrrolopyrrole (DPP) derivatives, owing to their strong light absorption and thermal and photochemical stability, as well as good charge transport properties, have been widely explored for developing high performance organic/polymeric semiconductors. 30-41 DPP-based conjugated donoracceptor polymers have been prepared and found to show p-type, n-type and even ambipolar semiconducting behaviors, depending on the features of the donor units and the connection manner of the donor and DPP units.…”

“…In fact, many quinoid molecules were found to show promising semiconducting properties, mostly as n-type organic semiconductors. 15,20–29…”