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The derivatization of perylenediimides (PDIs) by bay decoration is essential for the development of PDI‐based semiconductors owing to their excellent photoelectric properties. Herein, four bis‐azabenz‐annulated PDIs (bis‐AzaBPDIs) are concisely synthesized in high yields through ultraviolet‐induced photocyclization, where the reaction processes including aldimine condensation, cyclization, and oxidative re‐aromatization are investigated. The optical characterizations and theoretical simulation reveal that the unique properties of the four bis‐AzaBPDIs are comparable to their parent PDI. Organic field effect transistors with compounds 2, 3, or 4 as active layers indicated that all compounds showed unipolar electron transport properties with the mobilities of 1.1×10−3, 5.8×10−4, and 8.5×10−6 cm2 V−1 s−1, respectively. These results suggest the great potential of bis‐AzaBPDIs as organic semiconductors. The easy preparation approach reported in this work would renew research interest in developing bis‐AzaBPDI‐based optoelectronic molecules. [ABSTRACT FROM AUTHOR]

Graphical abstract Abstract Direct C-H arylation is an approximate tool for synthesis of thiophene-diketopyrrolopyrrole (DPP) derivatives, because of better atomic economy, fewer synthetic steps and being environmental friendly. In this work, DPP containing linear structured small molecule TBT(DPPT 2) 2 are facilely synthesized in high yield by the C-H direct arylation, other small molecule TBT(DPP) 2 are synthesized thought stille cross-crouping reaction. Thermal, optimized geometries, electrochemical, photo-physical properties and film morphology of two materials are studied and solution-coated organic field effect transistors (OFETs) are preparated. TBT(DPPT 2) 2 have wider band gaps and enhanced electronic defects compare to TBT(DPP) 2. Both TBT(DPP) 2 and TBT(DPPT 2) 2 demonstrated typical p-type transport with average hole mobility of 1.26 × 10−3 and 9.58 × 10-4 cm2 V-1 s-1 respectively. [ABSTRACT FROM AUTHOR]

Organic photovoltaic materials incorporating either chlorine atoms or ester groups have been studied as replacement strategy for fluorinated compounds. However, the characteristics of such materials when used in organic field-effect transistors (OFETs) remain unclear. The present work synthesized three polymers via the copolymerization of diketopyrrolopyrrole (DPP) with monothiophene units having no substituents or incorporating either chlorine atoms or ester groups. All three materials were found to have similar photophysical and electrochemical properties even though their repeating units had different substituents. The maximum hole mobility values for the polymer specimens were determined to be 0.37 cm2 V−1 s−1. The introduction of chlorine into the DPP-based polymer generated an amorphous semiconductor material that makes it a very promising candidate for commercial OFETs since its properties are independent of fabrication conditions. The new polymeric semiconductors demonstrated herein suggest the viability of such materials with regard to incorporation in organic field-effect transistors. [Display omitted] •Both ester groups and chlorine atoms were successfully introduced into DPP-based polymers. •Chlorination and esterification applied to polymeric OFET materials •The introduction of chlorine into the DPP-based polymer generated an amorphous semiconductor material. [ABSTRACT FROM AUTHOR]

Development of well-conjugated building blocks by a concise and efficient synthetic procedure is crucial for organic electronics. In particular, for A–DA′D–A-type (A = donor and D = acceptor) organic semiconductors, which are the most popular and successful small molecular acceptors, the limited number DA′D fused cores limits the variety of these molecules. Herein, we report a new A–DA′D–A-type small molecule, TIIC, containing an entirely new DA′D fused core. The complete synthetic procedure, including a well-designed photocyclization step, resulted in above 50% total yield over five steps. TIIC shows strong light absorption in the complete visible region because of the extended π-conjugation and strong intramolecular charge transfer. The deep lowest unoccupied molecular orbital energy level (−4.0 eV) of TIIC, which indicates the n-type semiconductor property, was further confirmed by the organic field-effect transistor performance with unipolar electron mobility of 3.51 × 10−4 cm2 V−1 s−1. [Display omitted] • A new A–DA′D–A-type small molecule, TIIC, was developed. • A total yield of 50.5% over five steps was achieved for TIIC. • TIIC shows strong light absorption and unipolar electron-transport properties. [ABSTRACT FROM AUTHOR]