Synlett
DOI: 10.1055/a-2716-3047
Letter

Sulfur-Mediated Synthesis of 2-Aryl-4(3H)-quinazolinones from 2-Aminobenzamides and Aryl Alcohols via KO t Bu-promoted Oxidative Condensation

Authors

  • Ngoc Binh Vo

    1   Institute of Chemistry, Vietnam Academy of Science and Technology, Hanoi, Viet Nam
  • Le Thanh Hang Nguyen

    2   School of Chemistry and Life Sciences, Hanoi University of Science and Technology, Hanoi, Viet Nam
  • Le Anh Nguyen

    1   Institute of Chemistry, Vietnam Academy of Science and Technology, Hanoi, Viet Nam
    3   Graduate University of Science and Technology, Vietnam Academy of Science and Technology, Cau Giay, Hanoi, Viet Nam
  • Dang Quang Le

    4   Institute of Materials Science, Vietnam Academy of Science and Technology, Hanoi, Viet Nam
  • Quoc Anh Ngo

    1   Institute of Chemistry, Vietnam Academy of Science and Technology, Hanoi, Viet Nam

Funding Information This research is funded by Vietnam National Foundation for Science and Technology Development (NAFOSTED) under grant number 104.01-2020.49.


Graphical Abstract

Abstract

Here, we report a simple protocol for the oxidative cyclization of 2-aryl-4(3H)-quinazolinones from 2-aminobenzamides and aryl alcohols promoted by KO t Bu, with S8/DMSO as the oxidant. This reaction has advantages such as easy-to-find starting materials, stability, and can be carried out under simple heating conditions without requiring transition metal catalysts, and is scalable. This method shows good tolerance to functional groups, including halogen, methoxy, and trifluoromethyl groups, as well as heterocyclic rings such as thiophene and pyridine in moderate to high yields (up to 92% yield). Furthermore, control experiments showed that the key step of this reaction involves the dehydrogenation of benzyl alcohol by an active sulfur species to the benzaldehyde intermediate, followed by oxidative condensation with 2-aminobenzamide.

Supplementary Material



Publication History

Received: 22 September 2025

Accepted: 30 September 2025

Article published online:
18 November 2025

© 2025. Thieme. All rights reserved.

Georg Thieme Verlag KG
Oswald-Hesse-Straße 50, 70469 Stuttgart, Germany