Oxindoles Stolle oxindole synthesis

Indole synthesis from anilines and glyoxal (Hinsberg), oxindole synthesis from anilines and a-haloacyl halides (Stolle) (see 1st edition). 

The Stolle Oxindole Synthesis (the Stolle Reaction) " refers to the conversion of a-chloroacyl chlorides (1) to oxindoles (3) in the presence of a Lewis acid. The reaction occurs via amide formation and subsequent annulation via an intramolecular Friedel-Crafts alkylation. 

In a very interesting application of the Stolle oxindole synthesis, reaction of (9-acylated-A-glycosylphenylamine with oxalyl chloride followed by deprotection gave the corresponding hexopyranosylisatins 23-25. ... 

From 1913 to 1930, R. Stolle published several manuscripts describing the synthesis of oxindoles from anilines and a-chloroacyl chlorides. His typical substrates were chloroacetanilides or the corresponding MA -diphenylamide. The manuscripts also described the synthesis of isatines (2,3-dioxindoles) from arylamines and oxalyl chloride. The reactions require high temperatures (typically > 150 °C) to complete the cyclization step. 

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