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Updated: May 31, 2026

Facile Preparation of 4-Substituted Quinazoline Derivatives
Published on: February 15, 2016
An easy entry into 2-halo-3-aryl-4(3H)-quinazoliniminium halides from heteroenyne-allenes
Vijaya Kumar Naganaboina1, Kusum Lata Chandra, John Desper
1Department of Chemistry, Kansas State University, 213 CBC Building, Manhattan, Kansas 66506-0401, USA.
Abstract:
An efficient three-step synthesis of 2-halo-3-aryl-4(3H)-quinazoliniminium halides from commercially available materials is described. Upon reaction with hydrogen halides, generated in situ from a Lewis acid (MX) and trace water, a variety of easily accessible heteroenyne-allenes underwent facile intramolecular cyclization to afford the title compounds in good yields. The method is highly versatile and provides a general way to construct quinazoliniminium ring systems with a variety of different substitutions.
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