Beilstein J. Org. Chem.2009,5, No. 55, doi:10.3762/bjoc.5.55
] as starting material, dibenzo[d,d′]benzo[1,2-b:4,3-b′]dithiophene, a [5]heterohelicene, was synthesized efficiently in 60% yield via formylation and McMurry reaction. Cyclopenta[1,2-b:4,3-b′]bis(benzo[d]thiophen)-6-one, another interesting helical ketone, was also prepared in 79% yield via
deprotonation and ketonization of 3,3′-bi[benzo[b]thiophenyl]. In addition, the single-crystal structure of dibenzo[d,d′]benzo[1,2-b:4,3-b′]dithiophene and UV–vis spectra of both title compounds are described.
Keywords: crystal structure; cyclopenta[1,2-b:4,3-b′]bis(benzo[d]thiophen)-6-one; dibenzo[d,d′]benzo
], have been developed and tested as active semiconducting channels in OFET devices due to their structural resemblance to pentacene [14] which possesses very high field-effect mobility (~3.0 cm2 V−1 s−1) for OFET devices. However, one of the possible analogs, dibenzo[d,d′]benzo[1,2-b:4,3-b′]dithiophene