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Updated: Sep 24, 2025

Facile Preparation of 4-Substituted Quinazoline Derivatives
Published on: February 15, 2016
Pyridine-2-carboxylic acid as an effectual catalyst for rapid multi-component synthesis of
Mayank G Sharma1, Ruturajsinh M Vala1, Hitendra M Patel1
1Department of Chemistry, Sardar Patel University University Campus, Vallabh Vidyanagar 388 120 Gujarat India hm_patel@spuvvn.edu.
Abstract:
Green synthesis of pyrazolo[3,4-b]quinolinones was designed using bioproduct pyridine-2-carboxylic acid (P2CA) as a green and efficient catalyst. The multi-component reaction of aldehydes, 1,3-cyclodiones and 5-amino-1-phenyl-pyrazoles regioselectively produced pyrazolo[3,4-b]quinolinones in excellent yield (84-98%). Recyclization of the catalyst was also investigated. The electronic effect of the various substituents in aromatic rings indicated that the reaction proceeded through the carbocation intermediate. This newly designed protocol very quickly constructed products conventionally under milder conditions.
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