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Updated: Jun 14, 2025

Facile Preparation of 4-Substituted Quinazoline Derivatives
Published on: February 15, 2016
Manganese Complex-Catalyzed (De)hydrogenative Cyclization toward the Selective Synthesis of 2-Substituted and
Debjyoti Pal1, Bitan Sardar1, Avijit Mondal1
1Department of Chemistry, Indian Institute of Technology-Guwahati, Kamrup, Assam 781039, India.
Abstract:
Herein, we describe bifunctional NNO-Mn(I)-catalyzed switchable synthesis of 3-benzyl-2-phenylquinolin-4(1H)-one and 2-phenylquinolin-4(1H)-one and their derivatives via (de)hydrogenative annulation of a host of alcohols with diverse amino acetophenones. To expand the versatility of our catalytic protocol, we conducted postsynthetic modification featuring bioactive compounds and synthesized 4-quinolones with antibiotic properties. Control and kinetic experiments were carried out to validate the mechanistic analysis, demonstrating that C-alkylation is preferred over N-alkylation in the synthesis of both heterocycles.
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