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Protocol for the Synthesis of Ortho-trifluoromethoxylated Aniline Derivatives
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Regioselective ortho-functionalization of bromofluorenecarbaldehydes using TMPMgCl·LiCl
Dominik Göbel1, Nils Clamor, Boris J Nachtsheim
1University of Bremen, Department of Organic and Analytical Chemistry, Leobener Straße 7, 28359 Bremen, Germany. nachtsheim@uni-bremen.de.
Organic & Biomolecular Chemistry
|May 23, 2018
Summary
A new method regioselectively functionalizes 7-bromofluorene-2-carbaldehydes at the C3 position. This provides rapid access to novel, highly functionalized fluorene derivatives and organic phosphorescent dyes.
Area of Science:
- Organic Chemistry
- Materials Science
Background:
- Fluorene derivatives are important organic chromophores.
- Developing efficient methods for functionalizing fluorenes is crucial for creating new materials.
Purpose of the Study:
- To develop a highly regioselective method for functionalizing 7-bromofluorene-2-carbaldehydes at the C3 position.
- To synthesize novel, highly functionalized fluorene derivatives and organic phosphorescent dyes.
Main Methods:
- Directed ortho-metallation (DoM) strategy using TMPMgCl·LiCl.
- Reaction of in situ generated metalated species with various electrophiles.
Main Results:
- Successful regioselective functionalization at the C3 position of 7-bromofluorene-2-carbaldehydes.
- Preparation of highly functionalized fluorene derivatives.
- Fast access to novel organic phosphorescent dyes.
Conclusions:
- The developed DoM strategy is effective for regioselective C3 functionalization of 7-bromofluorene-2-carbaldehydes.
- This method offers a facile route to novel fluorene-based organic phosphorescent dyes.
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