A Novel and Efficient Approach to (Z)-1,2-Bis(benzodithienyl)ethene ­Precursors of Tetrathia[7]helicenes

Abstract

A new and efficient method for the ‘one-step’ synthesis of (Z)-1,2-bis(benzodithienyl)ethenes has been set up using double Suzuki coupling between stereochemically defined diboronic acid esters and 2-iodo-benzodithiophene. The new Z-alkenes thus obtained can be easily and efficiently photochemically cyclised to the newly substituted tetrathia[7]helicenes.

Key words

coupling - helical structures - fused ring systems - (Z)-1,2-bis(benzodithiophenyl)ethenes - thiahelicenes

References

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Sigma-Aldrich company sells several (Z)-diboronic acid esters.