Synthesis of Functionalized Carbon-Sulfur [5]Helicene: Pd-Catalyzed Negishi Cross-Coupling Between the β-Positions of Thiophenes

Abstract

Octyl- and bromo-substituted carbon-sulfur [5]helicene was prepared in several steps starting from either thiophene or 3-bromothiophene. Pd-catalyzed Negishi cross-coupling between the β-positions of thiophenes was one of the key steps in the synthesis.

helical structures - cross-coupling - alkylthiophene - ­helicene - oligothiophene

References

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