Asymmetric synthesis of Bis-indoles and Indole Derivatives aided by Chiral Phosphoric acid ion pairing

Due to the significance of the indole core within natural products, synthetic efforts for better methodology has been an active area of research within the synthesis field. While there is plenty of literature on the topic, there is always a need for asymmetric variants. The candidate first demonstrates a facile, amenable, and mild method for the synthesis of bis-indoles and indole derivatives through a DDQ mediated cross dehydrogenative coupling. A substrate scope proves the reaction applicable to different types of functional groups. A series of chiral phosphoric acids were then screened in an effort to induce enantioselectivity. The candidate shows the results and findings from the screening of more than ten different CPAs. Lastly the candidate also attempts the synthesis of chiral bis-indoles through the chiral phosphoric acid catalyzed dehydration of a tertiary alcohol. Results and findings are reported from a series of reaction conditions.