Expanding Tetra[2,3-thienylene]-Based Molecular Muscles to Larger [4n]Annulenes

Abstract

The synthesis, X-ray structure, and predicted redox-induced conformational dynamics of a thiophene-fused [12]annulene is reported. Regiospecific halogenation of the thiophene ring system and transition-metal catalyzed cross-couplings are key elements in the synthetic strategy. It is predicted (B3LYP/6-31G*) that redox-induced conformational changes yield significant dimensional changes in this annulene, thus establishing it as a candidate for single molecule actuation.

Key words

annulenes - thiophene - cross-coupling - actuators - macrocycles

References

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All calculations were performed using Titan software; Schrödinger, Inc.; 1500 SW First Avenue, Suite 1180, Portland, Oregon 97201, USA

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Crystallographic data has been deposited in the Cambridge Crystallographic Data Centre Database.