Acene-thiophenes

Merlo, J. A. et al., /)-Channel organic semiconductors based on hybrid acene-thiophene molecules for thin-fibn transistor applications, J. Am. Chem. Soc., 127, 3997, 2005. 

Merlo, J.A. et al., p-channel organic semiconductors based on hybrid acene-thiophene... 

Nicolas, Y. et al.. Synthesis of a Thermally Stable Hybrid Acene-Thiophene Organic... 

Reports from 3M [46] and from Lucent Technologies [47] have indicated that combining thiophenes and acenes may also be a promising approach. The thiophene systems are somewhat easier to synthesize and purify, because of their greater solubility, but the acenes are typically higher-performing. The combination of the two has shown some intriguing initial results. 

Relating the cohesive energy to the number of carbon atoms per molecule one finds very similar results for the acenes (85, 79, 79, and 76 meV/C atom) and phenylenes (82, 80, 79, 79 meV/C atom), while the presence of sulfur atoms in the thiophenes increases the cohesive energies by roughly 10%. 

Recently, an acene fused-thiophene hybrid, p-channel semiconductor using a soluble precursor in which the solubility originates from trimethylsilyl groups was reported.[256] The elimination of two trimethylsilyl groups from the soluble precursor is accomplished through treatment with tetrabutylammonium fluoride in pyridine to give 43e. OTFTs made by thermally evaporated 43e showed mobility of 10 cm V s . ... 

The facile one-pot preparation of substituted dibenzothiophene S,S-dioxides and fluorenones were carried out by the Diels—Alder reaction ofbenzo[c]thiophenes. Photophysical properties of representative seven-and nine-membered dibenzothiophene S.S-dioxides acenes were also reported (14OL3068). 

Tetraiodothiophene was obtained from thiophene by applying iodine together with iodic acid in a mixture of acetic acid, water, carbon tetrachloride and sulfuric acid in ratio 5 2 1 0.1 (Scheme 79) [121]. The yellow solid was isolated in 65% yield and was used for the synthesis of sulfur-containing acenes [121]. 

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