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Solid-phase Synthesis of [4.4] Spirocyclic Oximes
Published on: February 6, 2019
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ipso-Cyclization: an emerging tool for multifunctional spirocyclohexadienones
Chada Raji Reddy1, Santosh Kumar Prajapti, Kamalkishor Warudikar
1Division of Natural Products Chemistry, CSIR-Indian Institute of Chemical Technology, Hyderabad 500 007, India. rajireddy@iict.res.in.
Organic & Biomolecular Chemistry
|March 25, 2017
Summary
Intramolecular ipso-annulation offers a powerful route to spirocyclic compounds with quaternary carbons. These versatile spirocyclic compounds are valuable synthons for building complex molecular architectures.
Area of Science:
- Organic Chemistry
- Synthetic Chemistry
Background:
- Spirocyclic compounds, featuring a central quaternary carbon atom, are prevalent in natural products and pharmaceuticals.
- Efficient synthetic methodologies are crucial for accessing these complex structures.
Purpose of the Study:
- To review various intramolecular ipso-annulation strategies for synthesizing spirocyclohexadienones.
- To highlight the synthetic utility of these spirocyclic compounds as building blocks for complex molecules.
Main Methods:
- Literature review of intramolecular ipso-cyclization reactions.
- Analysis of synthetic approaches yielding spirocyclohexadienones.
- Evaluation of the application of spirocyclic compounds in further synthesis.
Main Results:
- Several effective intramolecular ipso-annulation methods have been developed.
- A diverse range of spirocyclohexadienones can be accessed through these approaches.
- Spirocyclic compounds derived from ipso-annulation are demonstrated as key intermediates.
Conclusions:
- Intramolecular ipso-annulation is a valuable strategy for constructing spirocyclic frameworks.
- The synthesized spirocyclic compounds serve as versatile synthons for complex molecule synthesis.
- This review consolidates key methods and applications in spirocycle synthesis.
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