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Updated: Aug 6, 2026

Facile Preparation of 4-Substituted Quinazoline Derivatives
Published on: February 15, 2016
Multicomponent Condensation Reactions via ortho-Quinone Methides
Emily E Allen1, Calvin Zhu1, James S Panek1
1Department of Chemistry, Center for Molecular Discovery (BU-CMD), Life Science and Engineering Building, Boston University , 24 Cummington Mall, Boston, Massachusetts 02215, United States.
Abstract:
Iron(III) salts promote the condensation of aldehydes or acetals with electron-rich phenols to generate ortho-quinone methides that undergo Diels-Alder condensations with alkenes. The reaction sequence occurs in a single vessel to afford benzopyrans in up to 95% yield. The reaction was discovered while investigating a two-component strategy using 2-(hydroxy(phenyl)methyl)phenols to access the desired ortho-quinone methide in a Diels-Alder condensation. The two-component condensation also afforded the corresponding benzopyran products in yields up to 97%. Taken together, the two- and three-component strategies using ortho-quinone methide intermediates provide efficient access to benzopyrans in good yields and selectivities.
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