title: A successful chemical strategy to induce oligothiophene self-assembly into fibers with tunable shape and function.
abstract: Functional supramolecular architectures for bottom-up organic nano- and microtechnology are a high priority research topic. We discovered a new recognition algorithm, resulting from the combination of thioalkyl substituents and head-to-head regiochemistry of substitution, to induce the spontaneous self-assembly of sulfur overrich octathiophenes into supramolecular crystalline fibers combining high charge mobility and intense fluorescence. The fibers were grown on various types of surfaces either as superhelices or straight rods depending on molecular structure. Helical fibers directly grown on a field effect transistor displayed efficient charge mobility and intrinsic 'memory effect'. Despite the fact that the oligomers did not have chirality centers, one type of hand-helicity was always predominant in helical fibers, due to the interplay of molecular atropisomerism and supramolecular helicity induced by terminal substituents. Finally, we found that the new sulfur overrich oligothiophenes can easily be prepared in high yields through ultrasound and microwave assistance in green conditions.
authors.affiliation: Istitute for Organic Synthesis and Photoreactivity (ISOF-CNR), National Research Council, Via Gobetti 101, 40129 Bologna, Italy.
authors.forename: Francesca
authors.initials: F
authors.lastname: Di Maria
authors.forename: Pasquale
authors.initials: P
authors.lastname: Olivelli
authors.forename: Massimo
authors.initials: M
authors.lastname: Gazzano
authors.forename: Alberto
authors.initials: A
authors.lastname: Zanelli
authors.forename: Mariano
authors.initials: M
authors.lastname: Biasiucci
authors.forename: Giuseppe
authors.initials: G
authors.lastname: Gigli
authors.forename: Denis
authors.initials: D
authors.lastname: Gentili
authors.forename: Pasquale
authors.initials: P
authors.lastname: D'Angelo
authors.forename: Massimiliano
authors.initials: M
authors.lastname: Cavallini
authors.forename: Giovanna
authors.initials: G
authors.lastname: Barbarella