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Updated: Jun 22, 2025

Facile Preparation of 4-Substituted Quinazoline Derivatives
Published on: February 15, 2016
Leveraging in situ N-tosylhydrazones as diazo surrogates for efficient access to pyrazolo-[1,5-c]quinazolinone
Jun Yan1, Pascal Retailleau2, Christine Tran1
1Department of Chemistry and Medicinal Chemistry, Université Paris-Saclay, CNRS, BioCIS, 91400 Orsay, France. abdallah.hamze@universite-paris-saclay.fr.
Abstract:
We developed a transition metal-free methodology for the construction of pyrazoloquinazolinone derivatives. The strategy involves a one-pot reaction wherein the N-tosylhydrazone and its corresponding diazo derivative are generated in situ, followed by an intramolecular 1,3-dipolar cycloaddition-ring expansion to provide the pyrazolo-[1,5-c]quinazolinone motif. This approach enables straightforward access to a diverse range of highly functionalized N-heterocyclic compounds in good yields (up to 92%).
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