research article
Synthesis of 3-Acyloxyindolenines by TiCl3-Mediated Reductive Cyclization of 2-(ortho-Nitroaryl)-Substituted Enol Esters
September 19, 2022
In the presence of TiCl3, the reductive cyclization of tetrasubstituted enol esters bearing a 2-(ortho-nitroaryl) substituent affords 3-acyloxy-2,3-disubstituted indolenines in good yields. A domino process involving the partial reduction of nitro to a nitroso group followed by 5-center-6π electrocyclization, 1,2-acyloxy migration, and the further reduction of the resulting nitrone intermediate accounts for the reaction outcome. The so-obtained indolenines are converted smoothly to 2,2-disubstituted oxindoles via a sequence of saponification and semipinacol rearrangement.
Type
research article
Author(s)
Date Issued
2022-09-19
Published in
Volume
24
Issue
38
Start page
7004
End page
7008
Editorial or Peer reviewed
REVIEWED
Written at
EPFL
EPFL units
Available on Infoscience
October 10, 2022
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