Semiconductors selenophenes

A new class of semiconductors for organic field-effect transistors (FET) has been developed and studied. Thus metalation of the 1,4-dibromobenzene derivative 141, followed by Introduction of the appropriate chalcogens gave the fused systems 142, which displayed promising FET performances, in particular the selenophene derivative <04JA5084>. 

Although polythiophenes are best utilized as solution-processable high-performance p-type semiconductors [102], polyselenophenes are of no use as FET materials because of their insolubility. However, it was recently reported that selenophene-containing copolymers 47-50 could form thin films with a solution-processable method and showed p-channel FET responses with hole mobilities of the order of 10 " -10 cm V s [103]. When the thin films were annealed after spin coating, the mobilities were enhanced by one order of magnitude. 

Because isoindigo homopolymer is a typical n-type semiconductor, [14] in order to obtain p-type isoindigo-based polymers, electron-rich groups should be introduced to increase the HOMO level of the desired polymers. The donor-acceptor interactions of electron-deficient isoindigo units and electron-rich units may enhance the interchain ti-ti stacking interactions. Selenophene-(2-4) and thiophene-containing (2-5 to 2-11) units are used to construct the copolymers (Scheme 2.2). Units 2-4—2-7 and unit 2-10 are centrosymmetric, and units 2-8, 2-9 and 2-11 are... 

---