C3 versus C5 Regioselectivity in the Intramolecular Dehydrative Friedel–Crafts Alkylation of Indole C4-Tethered Carbinols

Organic Letters, Journal Year: 2025, Volume and Issue: unknown

Published: March 3, 2025

Described herein is a mild catalytic dehydrative Friedel-Crafts alkylation of 1,1-diarylalkanols─a challenging reaction with exceedingly rare previous success, presumably because the unfavorable steric hindrance around reactive centers and competitive E1 reaction. Executing in an intramolecular fashion benefiting from high nucleophilicity indole, we have successfully utilized this synthesizing 3,4-fused indoles. Interestingly, strategy could also be applied to access 4,5-fused indoles via modification tether connecting alcohol indole moieties.

Language: Английский

Regio- and Enantioselective N-Heterocyclic Carbene-Catalyzed Annulation of Aminoindoles Initiated by Friedel–Crafts Alkylation

Organic Letters, Journal Year: 2024, Volume and Issue: 26(33), P. 6993 - 6998

Published: Aug. 8, 2024

Chiral indoles annulated on the benzene ring are unique and significant in natural medicinal compounds. However, accessing these enantioenriched molecules has often been overlooked. The present study introduces an organocatalytic protocol to access compounds efficiently, demonstrated by substrate scope, functional group tolerance, using only 1 mol % of a chiral conjugated acid catalyst. Additionally, explores regioselectivity, gram-scale reactions, follow-up transformations, underscoring method's potential.

Language: Английский