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Updated: Jun 13, 2026
11:51
Facile Preparation of 4-Substituted Quinazoline Derivatives
Published on: February 15, 2016
Recent Breakthroughs in Cyclizations of Ortho-Quinone Methides
Dongyi Wang1, Jiahao Guo1, Linzhi Tan1
1School of Environmental and Chemical Engineering, Wuyi University, Jiangmen 529020, China.
Molecules (Basel, Switzerland)
|June 12, 2026
Summary
Ortho-quinone methides (o-QMs) are reactive intermediates enabling complex molecule synthesis via [4 + n] cyclizations. This review highlights recent advances, challenges, and future opportunities in o-QM chemistry for organic synthesis.
Area of Science:
- Organic Chemistry
- Synthetic Chemistry
Background:
- Ortho-quinone methides (o-QMs) are versatile intermediates with a unique polarized electronic structure.
- Their electron-deficient quinoid ring and electrophilic exocyclic unit make them powerful C4 synthons.
Purpose of the Study:
- To provide a comprehensive overview of recent advances in ortho-quinone methide chemistry.
- To systematically discuss reaction design, mechanistic insights, and synthetic applications of o-QMs in [4 + n] cyclizations.
Main Methods:
- Review of recent literature on o-QM reactions.
- Systematic discussion of various [4 + n] cyclization modes ([4 + 1], [4 + 2], [4 + 3]).
- Analysis of reaction design, mechanistic insights, and synthetic applications.
Main Results:
- Ortho-quinone methides facilitate the rapid construction of complex carbocyclic and heterocyclic frameworks.
- [4 + n] cyclizations involving o-QMs are effective strategies for synthesizing privileged scaffolds.
- Recent advances showcase diverse synthetic applications and mechanistic understanding.
Conclusions:
- Ortho-quinone methides are crucial for constructing complex molecular architectures.
- Further innovation is needed in catalytic systems, asymmetric synthesis, and precursor development.
- This review offers insights into the state of the art and future directions in o-QM chemistry.
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