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Mechanisms of photo‐catalytic decarboxylative reaction between 2‐phenylbutanoic acid and 1,4‐dicyanobenzene (1,4‐DCB) have been investigated with the method of M06‐L/ma‐def2‐TZVP in the domain‐decomposition COnductor‐like Screening MOdel (ddCOSMO) of CH3CN. The TDDFT calculations of 1,4‐DCB and 2‐phenylbutanoic acid model have revealed the photo‐excitation and electron transfer process, which could agree with experimental phenomena. The computational results of Gibbs free energy profiles show that the R1+1,4‐DCB model could achieve the decarboxylative reaction under the 300 nm UV light in path c. And paths a and b indicate that HPO42− and K2HPO4 could assist the whole reaction process with lower energy barrier successfully. Results would provide valuable insights into these types of interactions and related ones. [ABSTRACT FROM AUTHOR]

Two novel isomeric polymers P(DPPT-TT) and P(DPPTT-T) based on thiophene-flanked diketopyrrolopyrrole, thieno[3,2-b]thiophene and thiophene building units were designed and synthesized via a new skeletal isomerization strategy. This study emphasizes on the impact of this skeletal isomerization on the photoelectric properties and organic field-effect transistor (OFET) performances of the resulting isomeric polymers. Both polymers show similar light absorption properties and excellent thermostability and have a comparable molecular weight. They also display typical p-type characteristics in air-tested OFETs. However, P(DPPTT-T) exhibits significantly better OFET performances. In particular, its average hole mobility reaches 2.14 cm2 V−1 s−1, triple that of P(DPPT-TT). The higher mobility of P(DPPTT-T) might be attributed to the interconnected, smooth and thicker nanofibrillar network morphology and the relatively higher crystallinity of its thin films, and its conjugated chains possess a smaller π–π stacking distance. [ABSTRACT FROM AUTHOR]

The efficient design and synthesis of new tert-butoxycarbonyl (t-Boc) and t-Boc-removed diketopyrrolopyrrole (DPP) polymers with regioregular conjugated backbones via a new route of combining random copolymerization and the classical t-Boc precursor approach are reported. The resulting new type of DPP polymer, named P(40/1)-H, is found to possess good solubility, film-forming ability, and reasonable optoelectronic properties. Importantly, it displays a significantly improved field-effect mobility (∼0.91 cm2 V−1 s−1) as compared to the recognized reference polymer P(100/0) (∼0.56 cm2 V−1 s−1), which indicates partially removing the long branched alkyl side chains of a regioregular conjugated backbone based DPP polymer is an alternative new strategy of molecular design for enhancing field-effect carrier mobility. [ABSTRACT FROM AUTHOR]

We report two new regioregular and regioirregular model copolymer acceptors based on selenophene and perylenetetracarboxylic diimide moieties, respectively, named RR-P(SePDI) and RI-P(SePDI), which were synthesized to study how regioregularity impacts the properties of resulting polymers. The structural regioregularity impact on the performance of polymer-polymer solar cells (PPSCs) was highlighted. Both the copolymer acceptors displayed similar optoelectronic properties. The regioregular RR-P(SePDI) exhibited better and balance bulk charge-transport capability than regioirregular RI-P(SePDI) in active layer films. The typical PPSCs based on the regioirregular RI-P(SePDI) copolymer acceptor and the PTB7-Th polymer donor afforded average power conversion efficiencies (PCEs) of about 5.3%. Importantly, reasonably improved average PCEs of about 6.2% were provided by the blend active layer of new regioregular RR-P(SePDI) and PTB7-Th. These results highlight the significant and efficient strategy of rational control regioregularity of the polymer backbone to gain high PCE values in perylene diimide-based PPSCs.