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A series of copolymers containing a glycolated 1,4‐dithienyl‐2,3,5,6‐tetrafluorophenylene unit copolymerized with thiophene, bithiophene, thienothiophene and 1,2,4,5‐tetrafluorobenzene comonomer units were designed and synthesised by direct heteroarylation polymerisation. The optical, electrochemical, electrochromic and solid‐state structural properties of the copolymers were investigated. The copolymers exhibit stable redox properties in organic solvents and promising redox properties in thin film configuration with an aqueous electrolyte. Finally, the potential of the copolymers as active materials in organic electrochemical transistors (OECTs) was assessed, and promising performance was shown as an accumulation‐mode OECT material with a peak transconductance of 0.17 mS and a good on/off ratio of 105 for the thiophene copolymer. [ABSTRACT FROM AUTHOR]

To highlight the benefits of the organic dye PDI‐DPP‐PDI for use in fullerene‐free organic solar cells, herein is demonstrated how this material can meet scalability demands through a multigram scale direct heteroarylation coupling reaction, and performance demands through a post‐deposition solvent vapor annealing treatment. A solvent vapor annealing method has been utilized to screen a comprehensive selection of ethereal, aromatic, and chlorinated solvents. Upon transitioning to these eight alternative solvents, significant performance increase over the chloroform standard is noted for all solvents, with tetrahydrofuran and o‐dichlorobenzene leading to the highest performance devices post‐treatment. This trend, including an open‐circuit voltage greater than 1 V proved to be consistent with four different BDT‐based donor polymers, PTB7‐Th, PBDB‐T, J61, and TTFQx‐T1. The highest performing devices are achieved with PTB7‐Th and TTFQx‐T1, with PCEs reaching 6.2 and 5.7%, respectively, when tetrahydrofuran solvent vapor annealing is combined with interfacial modification of the ZnO electron‐transport layer. [ABSTRACT FROM AUTHOR]

Herein we report on the synthesis of an N-annulated perylene diimide (PDI) disubstituted thieno[3,4-c]pyrrole-4,6-dione (TPD) molecular acceptor (PDI–TPD–PDI) by direct heteroarylation (DHA) methods. Three sets of DHA conditions that explore the effects of solvent, temperature, and catalyst were employed to find the optimal conditions for the synthesis of two PDI–TPD–PDI derivatives. We then selected one PDI–TPD–PDI for use as a non-fullerene acceptor in organic solar cell devices with the donor polymer PBDB-T. Active layer bulk-heterojunction blends were modified using several post-deposition treatments, including thermal annealing, solvent vapour annealing, and high boiling solvent additives. It was found that active layers cast from o-dichlorobenzene with a 3% v/v diphenylether additive yielded films with adequate phase separation, and subsequently gave the best organic solar cell performance, with power conversion efficiencies greater than 3%.

This study reports the synthesis and characterization of poly(3-hexylthiophene) (P3HT) from a direct heteroarylation polymerization of two isomeric monomers, 2-bromo-3-hexylthiophene (monomer 1) and 2-bromo-4-hexylthiophene (monomer 2). Using the Herrmann-Beller catalyst along with P(o-NMe2Ph)3, the resulting polymers are obtained in excellent yields and exhibit a good number-average molecular weight (Mn of 33 and 16 kDa, respectively). Detailed ¹H NMR analyses reveal less than 1% of homocouplings and no evidence of β-branching. Dehalogenation is identified as the main chain termination step and preferentially occurs on monomer 2. The melting temperature (237 °C) and hole mobility (up to 0.19 cm² V-1⋅s-1) of the nearly defect-free P3HT obtained from this simple polymerization of monomer 1 are comparable, if not superior, to those obtained with commercially available GRIM and Rieke samples. [ABSTRACT FROM AUTHOR]

Abstract: 3-Benzoyl-4-(thien-2-yl)coumarins have been obtained in good yields according to the SN H addition–oxidation protocol, involving the diastereoselective addition of thiophenes at C-4 of 3-benzoylcoumarins under BBr3 catalysis, followed by oxidation of the intermediate 3,4-trans-3-benzoyl-4-(thien-2-yl)-3,4-dihydrocoumarins with DDQ. This two-step procedure can be regarded as nucleophilic substitution of hydrogen (SN H) on the heterocyclic ring of coumarins. [Copyright &y& Elsevier]

[Display omitted] • An array of rigid α-diimine palladium complexes were reported. • These palladium complexes efficiently promoted the direct C-H arylation under mild reaction conditions. • Cross-coupling of a variety of thiophene with heteroaryl bromides afforded excellent yields and high reigioselectivity. The direct C-H heteroarylation of thiophenes, promoted by rigid α-diimine palladium complexes is described. This approach exhibits broad substrate scopes with functional group tolerant, and proceeds with the formation of regioselective products. [ABSTRACT FROM AUTHOR]

A diketopyrrolopyrrole derivative was copolymerized with different electron-withdrawing units [i.e., thieno[3,4- c]pyrrole-4,6-dione ( TPD), bis(thieno[3,4- c]pyrrole-4,6-dione) ( BTPD), and 3,4-dicyanothiophene ( DCT)] using direct heteroarylation polymerization (DHAP) methodology. Alternating copolymers with low-lying frontier orbitals suitable for n-type semiconducting behavior were obtained. Under optimized conditions, polymerization reactions were reproducible and high number-average molecular weights ( Mn) were achieved. Density functional theory (DFT) calculations indicated that the structures with the lowest conformational energy had planar backbones. Preliminary results showed that these new low-bandgap materials exhibit good n-type behavior. [ABSTRACT FROM AUTHOR]

A new semiconducting polymer based on terthiophene-thienopyrrolodione alternating building blocks with a deep HOMO energy level (5.66 eV) is presented. The polymer is prepared by a direct heteroarylation polycondensation reaction, which is a low-cost and green alternative to the standard Stille coupling reaction and thus avoids any use of toxic stannyl derivatives. Integrating the polymer into bulk heterojunction solar cells with [6,6]-phenyl C71-butyric acid methyl ester ([70]PCBM) leads to a PCE of over 6% and a high open-circuit voltage of up to 0.94 V. To obtain these results a unique processing additive, 1-chloronaphthalene, is used, and a relatively low concentration of [70]PCBM is used in the blend solution. [ABSTRACT FROM AUTHOR]

Herein we report on the synthesis of an N-annulated perylene diimide (PDI) disubstituted thieno[3,4-c]pyrrole-4,6-dione (TPD) molecular acceptor (PDI–TPD–PDI) by direct heteroarylation (DHA) methods. Three sets of DHA conditions that explore the effects of solvent, temperature, and catalyst were employed to find the optimal conditions for the synthesis of two PDI–TPD–PDI derivatives. We then selected one PDI–TPD–PDI for use as a non-fullerene acceptor in organic solar cell devices with the donor polymer PBDB-T. Active layer bulk-heterojunction blends were modified using several post-deposition treatments, including thermal annealing, solvent vapour annealing, and high boiling solvent additives. It was found that active layers cast from o-dichlorobenzene with a 3% v/v diphenylether additive yielded films with adequate phase separation, and subsequently gave the best organic solar cell performance, with power conversion efficiencies greater than 3%. [ABSTRACT FROM AUTHOR]