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Updated: May 31, 2026
Protocol for the Synthesis of Ortho-trifluoromethoxylated Aniline Derivatives
Published on: January 19, 2016
Asymmetric fluoroallylboration of aldehydes
P Veeraraghavan Ramachandran1, Agnieszka Tafelska-Kaczmarek, Kaumba Sakavuyi
1Herbert C. Brown Center for Borane Research, Department of Chemistry, Purdue University, 560 Oval Drive, West Lafayette, Indiana 47907-2084, USA. chandran@purdue.edu
This study introduces a new method for creating chiral difluoroallylboronates and gem-difluorinated alcohols. These compounds are valuable building blocks in asymmetric synthesis, enabling access to complex fluorinated molecules.
Area of Science:
- Organic Chemistry
- Asymmetric Synthesis
- Organoboron Chemistry
Background:
- Previous methods for synthesizing difluoroallylboronates were limited.
- Chiral fluorinated compounds are important in medicinal chemistry and materials science.
Purpose of the Study:
- To develop a novel and efficient method for the synthesis of chiral γ,γ-difluoroallylboronates.
- To demonstrate the utility of these reagents in asymmetric fluoroallylboration reactions.
Main Methods:
- Homologation of benzyloxydifluorovinyllithium with chiral iodomethylboronates.
- Asymmetric fluoroallylboration of aldehydes using a chiral reagent derived from 2-phenylbornane-2,3-diol.
Main Results:
- Readily obtained a series of chiral γ,γ-difluoroallylboronates.
- Achieved good yields and high enantioselectivity (77-95% ee) in the synthesis of gem-difluorinated homoallyl alcohols.
- Prepared a chiral α-pyrone with >99% ee.
Conclusions:
- The developed method provides efficient access to valuable chiral difluorinated building blocks.
- This work expands the scope of asymmetric fluoroallylboration reactions.
- The methodology allows for the preparation of enantiomerically pure fluorinated compounds.
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