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Updated: Jun 16, 2026

Facile Preparation of 4-Substituted Quinazoline Derivatives
Published on: February 15, 2016
Phosphite-Promoted Generation of ortho-Quinodimethanes for Efficient and Scalable Benzannulation
Monther S Zreid1, Andrew J Cox1, Yuming Zhao1
1Department of Chemistry, Memorial University of Newfoundland, 45 Arctic Avenue, St. John's, Newfoundland and Labrador A1C 5S7, Canada.
None:
The classical Cava benzannulation suffers from high temperatures and poor solvent tolerance. We report a mild, room-temperature alternative using diethyl phosphite as a nucleophile. With diisopropylethylamine, smooth debromination generates reactive ortho-quinodimethanes for [4 + 2] cycloaddition with various dienophiles (e.g., quinones, alkenes, alkynes). This protocol is scalable, operationally simple, and even compatible with benzyne at -78 °C, enabling efficient synthesis of diverse aromatic structures.
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