Ring Synthesis of Isatins

An isatin can be readily prepared via the reaction of an aniline with chloral, the resulting product converted into an oxime, and this cyclised in strong acid. An alternative route to the oximinoacetanilide intermediates involves acylation of the aniline with 2,2-diacetoxyacetyl chloride and then reaction with hydroxylamine. °  

A-Dialkyl-anilines react with oxalyl chloride prodncing A-alkyl isatins.  

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