Pfitzinger synthesis from isatins

PFITZINGER Quinoline synthesis QumoHne-4-cartx)xyHc acids from isatin and a-methylene carbonyl compounds. 

The Pfitzinger reaction entails the synthesis of quinoline-4-carboxylic acids 2 via condensation of isatic acids formed from isatins 1 and a-methylene carbonyl compounds in the presence of strong aqueous bases. Subsequent decarboxylation can afford the corresponding quinolines. " ... 

PFITZINGER Quinoline synthesis ai ioline-4-cart xylic acids from isatin and o-methylene carbonyl compounds. 

Quinolines from isatins Pfitzinger-Borsche synthesis... 

Potassium hydroxide Quinoline-4-carboxylic acids from isatins Pfitzinger-Borsdie synthesis... 

The present review covers all the available published data on the Pfitzinger reaction beginning from the time of its discovery. The investigated material has been classified on the basis of the structure of the initial ketones separate sections cover the reactions of isatins with dialkyl ketones, keto acids, alkyl aryl ketones, and alkyl hetaryl ketones and also with cyclic ketones. Papers describing the synthesis of 4-quinolinecarboxylic acids by methods related to the Pfitzinger reaction are discussed in a separated section. 

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