A C2‐symmetric 7,8‐dioxa[6]helicene‐2,13‐diol was synthesized from readily available 2,7‐dihydroxynaphthalene on a gram scale. A high‐yielding synthetic strategy for the regioselective hydroxymethylation at the sterically most hindered C1 position of diol analogues was investigated. The dioxa[6]helicene backbone with configurationally stable helical enantiomers was synthesized, and these enantiomers were separated by HPLC on a chiral stationary phase. We also observed an unexpected domino Prins reaction. This is the first report of a domino Prins reaction occurring on a helicene. Along with the high‐yielding regioselective functionalization of dioxa[6]helicene analogues, the synthesis of a few cis‐7a,14c‐dihydro‐functionalized helicenoid diols substituted at the sterically most hindered C1 and C14 positions in their racemic forms was explored.

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The effect of aqueous ethanol medium on the outcome of a DielsÁAlder (DA) reaction with regard to yields, reaction time, and the stereoselectivity observed has been studied. When the reaction between anthrone and (R)-(')-N-a-methylbenzylmaleimide was carried out in aqueous ethanol in presence of achiral base no diastereoselectivity could be obtained. Moderate diastereoselectivity could be achieved in presence of chiral bases. Use of biodegradable aqueous ethanol solvent for the reaction and stereoselective nature of the reactions studied provide a greener approach.