Premium
A Route to Indoles via Modified Fischer Indole Intermediates from Sulfonanilides and Ketene Dithioacetal Monoxides
Author(s) -
Kinoshita Jun,
Baralle Alexandre,
Yoshida Akira,
Yanagi Tomoyuki,
Nogi Keisuke,
Yorimitsu Hideki
Publication year - 2020
Publication title -
asian journal of organic chemistry
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.846
H-Index - 44
eISSN - 2193-5815
pISSN - 2193-5807
DOI - 10.1002/ajoc.202000397
Subject(s) - ketene , chemistry , indole test , sigmatropic reaction , yield (engineering) , pummerer rearrangement , organic chemistry , medicinal chemistry , acetic anhydride , catalysis , materials science , metallurgy
An S−N variant of the N−N‐based Fischer indole synthesis has been developed. Treatment of sulfonanilides and ketene dithioacetal monoxides with a powerful acid anhydride provides N ‐sulfonyl‐2‐methylsulfanylindoles. The initial interrupted Pummerer reaction would yield the key S−N‐tethered precursor in situ that then undergoes [3,3] sigmatropic rearrangement, after which the endgame to the indole ring follows the Fischer manner.