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High ambipolar mobility emissive conjugated polymers (HAME‐CPs) are perfect candidates for organic optoelectronic devices, such as polymer light emitting transistors. However, due to intrinsic trade‐off relationship between high ambipolar mobility and strong solid‐state luminescence, the development of HAME‐CPs suffers from high structural and synthetic complexity. Herein, a universal design principle and simple synthetic approach for HAME‐CPs are developed. A series of simple non‐fused polymers composed of charge transfer units, π bridges and emissive units are synthesized via a two‐step microwave assisted C−H arylation and direct arylation polymerization protocol with high total yields up to 61 %. The synthetic protocol is verified valid among 7 monomers and 8 polymers. Most importantly, all 8 conjugated polymers have strong solid‐state emission with high photoluminescence quantum yields up to 24 %. Furthermore, 4 polymers exhibit high ambipolar field effect mobility up to 10−2 cm2 V−1 s−1, and can be used in multifunctional optoelectronic devices. This work opens a new avenue for developing HAME‐CPs by efficient synthesis and rational design. [ABSTRACT FROM AUTHOR]

A series of thienoisoindigo (TIG)‐based conjugated polymers (CPs) with high molecular weights are synthesized by direct arylation polycondensation (DArP) by using TIG derivatives as CBr monomer and multi‐halogenated thiophene derivatives, i.e., (E)–1,2‐bis(3,4‐difluorothien‐2‐yl)ethene (4FTVT), (E)–1,2‐bis(3,4‐dichlorothien‐2‐yl)ethene (4ClTVT), 3,3',4,4'‐tetrafluoro‐2,2'‐bithiophene (4FBT), and 3,3',4,4'‐tetrachloro‐2,2'‐bithiophene (4ClBT), as CH monomers. Density functional theory (DFT) calculations reveal the high selectivity between α‐CH bonds in 4FTVT, 4ClTVT, 4FBT, and 4ClBT and β‐CH bonds in TIG CBr monomer. All four resulting CPs exhibit low optical bandgaps of ca. 1.20 eV and ambipolar transport characteristics with both electron and hole mobility above 0.1 cm2 V−1 s−1 as elaborated with organic thin‐film transistors (OTFTs). The polymer TIG‐4FTVT delivers the best device performance. With this polymer, n‐channel OTFTs with electron mobility up to 1.67 cm2 V−1 s−1 and p‐channel OTFTs with hole mobility up to 0.62 cm2 V−1 s−1 are fabricated by modifying source/drain electrodes with polyethylenimine ethoxylated (PEIE) and MoO3, respectively, to selectively inject electrons and holes. [ABSTRACT FROM AUTHOR]