Fluorous TBAF: a convenient and selective reagent for fluoride-mediated deprotections
Santos Fustero1, Amador García Sancho, José Luis Aceña
1Departamento de Química Orgánica, Universidad de Valencia, E-46100 Burjassot, Spain. santos.fustero@uv.es
The Journal of Organic Chemistry
|July 11, 2009
Summary
A novel fluorous analogue of tetrabutylammonium fluoride (TBAF) enables efficient removal of silicon-based protecting groups. This method simplifies purification, yielding high-purity alcohols, amines, and carboxylic acids without chromatography.
Area of Science:
- Organic Chemistry
- Synthetic Chemistry
Background:
- Silicon-derived protecting groups are widely used in organic synthesis.
- Their removal often requires harsh conditions or extensive purification.
- Tetrabutylammonium fluoride (TBAF) is a common reagent for desilylation.
Purpose of the Study:
- To develop a fluorous analogue of TBAF for cleaner protecting group removal.
- To investigate the utility of fluorous TBAF in purification via fluorous solid-phase extraction.
- To explore the selective deprotection capabilities of fluorous TBAF on bifunctional molecules.
Main Methods:
- Synthesis of a fluorous analogue of TBAF.
- Application of fluorous TBAF for the removal of silicon-derived protecting groups.
- Purification of reaction products using fluorous solid-phase extractions.
- Assessment of selectivity in deprotection of bifunctional molecules.
Main Results:
- The fluorous TBAF analogue effectively removed silicon-derived protecting groups.
- Fluorous solid-phase extraction provided high purity of alcohols, amines, and carboxylic acids.
- Chromatographic separations were unnecessary.
- Selective deprotections were achieved on several bifunctional molecules due to moderate reactivity.
Conclusions:
- Fluorous TBAF offers a clean and efficient method for desilylation.
- The developed method simplifies purification processes in organic synthesis.
- Fluorous TBAF is a valuable tool for selective deprotection strategies.
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