Waghray, Deepali Vet, Christiaan de Karypidou, Konstantina Dehaen, Wim Oxidative Transformation to Naphthodithiophene and Thia[7]helicenes by Intramolecular Scholl Reaction of Substituted 1,2-Bis(2-thienyl)benzene Precursors We present here a strategy to synthesize a variety of substituted naphthodithiophene building blocks through DDQ/acid-mediated oxidative cyclizations. The versatility of the Scholl reaction using the DDQ/acid system was demonstrated by the preparation of a novel substituted tetrathia[7]­helicene where three new C–C bonds were formed in a one-pot procedure. The new DDQ/acid method was compared to the known strategies such as FeCl<sub>3</sub> oxidation and oxidative photocyclization. By protecting the 1,2-bis­(2-thienyl)­benzene precursors, it is possible to direct the intermediates to controlled cyclization and effectively suppressing the polymerization. The highly reactive α-position of the terminal thiophenes can allow for further functionalization. The efficient preparation of a variety of naphthodithiophene building blocks, the extension to a nonphotochemical synthesis of [<i>n</i>]­helicenes, and the ease of isolation of the products are arguments for the use of DDQ/acid system for this Scholl reaction. naphthodithiophene building blocks;variety;cyclization;strategy;DDQ;FeCl 3 oxidation;Scholl reaction;oxidative;Intramolecular Scholl Reaction;preparation 2013-11-15
    https://acs.figshare.com/articles/journal_contribution/Oxidative_Transformation_to_Naphthodithiophene_and_Thia_7_helicenes_by_Intramolecular_Scholl_Reaction_of_Substituted_1_2_Bis_2_thienyl_benzene_Precursors/2352634
10.1021/jo401807x.s001