Cross‐Dehydrogenative Coupling Polymerization via C−H Activation for the Synthesis of Conjugated Polymers

Abstract

Owing to their versatile (opto)electronic properties, conjugated polymers have found application in several organic electronic devices. Cross‐coupling reactions such as Stille, Suzuki, Kumada couplings, and direct arylation reactions have proved to be effective for their synthesis. More atom‐efficient oxidative direct arylation polymerization has also been reported for making homopolymers. However, growing interest toward donor‐acceptor polymers has led to the recent emergence of cross‐dehydrogenative coupling (CDC) polymerization to synthesize alternating copolymers without any prefunctionalization of monomers. Metal‐catalyzed cross‐coupling of two simple arenes via double C−H activation, or of an arene with an alkene via oxidative Heck‐type reaction have been used so far for CDC polymerization. In this article, we discuss the development of CDC polymerization protocols along with the relevant small molecule CDC reactions for an improved understanding of these reactions.

Discovery of Organic Optoelectronic Materials Powered by Oxidative Ar–H/Ar–H Coupling

“…Transition-metal-catalyzed oxidative Ar−H/Ar−H coupling polycondensation, also known as Oxi-DArP, provides an ideal approach to conjugated polymers. 15 Although the progression of Oxi-DArP has trailed behind direct arylation polycondensation (Ar−H/Ar−X), 125−127 the emergence of successful instances in the construction of high-performance polymeric materials is on the rise.…”

Polyconjugated Materials for Printed (Opto)Electronics: Introducing Sustainability

“…57 Direct arylation methods are becoming increasingly competitive with Stille and SM, also for the manufacturing of polyconjugated molecules and polymers. [136][137][138][139][140][141][142] We exploited the direct (hetero)arylation polymerization (DHAP) approach for the synthesis of a polymeric latent pigment derivative, aimed at mimicking the transport properties of the very popular electron-transporting material poly{[N,N′-bis(2-octyldodecyl)-naphthalene-1,4,5,8bis(dicarboximide)-2,6-diyl]-alt-5,5′-(2,2′-bithiophene)} (P(NDI2OD-T2). [143][144][145][146][147] Scheme 4 Synthetic pathway leading to the luminescent radicals PyPBTM, Py-PNBTM, and PyPhBTM…”

Green and sustainable synthesis of TPD-based donor–acceptor-type conjugated polymer photocatalysts for hydrogen production under visible light

“…Recently developed direct C-H/C-H coupling polycondensation, where C-C bond formation occurs directly from C-H bonds of the nonfunctionalized monomers, has enabled the greener and more sustainable synthesis of these polymers through the reduction of waste, elimination of toxic and harmful by-products, and through the reduction of overall synthetic steps. [31][32][33][34][35][36][37][38] Unfortunately, there are no examples of conjugated polymers prepared using such a polymerization method for photocatalytic hydrogen evolution so far.…”