Regioselectivity of Electrophilic Aromatic Substitution: Syntheses of 6- and 7-Sulfamoylindolines and -indoles

Article abstract of DOI:10.1021/jo00244a036

The previously reported chlorosulfonation of 1-acetyl-5-bromoindoline at the 7-position is in error.In actuality, the 6-substituted product is the sole regioisomer produced.This regiochemical assignment is based on NMR data and confirmed by X-ray analysis.We have prepared the first 7-sulfamoylindoline and the corresponding indole from indoline using the indoline nitrogen to direct sulfamoylation intarmolecularly to the 7-position.The new 7-substituted derivatives may prove to be important as intermediates to indole-based dyes and as herbicides.