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Carboxylic Acid Deoxyfluorination and One-Pot Amide Bond Formation Using Pentafluoropyridine (PFP).
William D G Brittain1, Steven L Cobb1
1Department of Chemistry, Durham University, South Road, Durham DH1 3LE, United Kingdom.
Organic Letters
|July 12, 2021
Summary
Pentafluoropyridine (PFP) enables efficient deoxyfluorination of carboxylic acids to acyl fluorides. This method also facilitates one-pot amide synthesis with high yields, offering a cost-effective route to amides.
Area of Science:
- Organic Chemistry
- Synthetic Chemistry
Background:
- Carboxylic acid derivatization is crucial in organic synthesis.
- Acyl fluorides are versatile intermediates but their synthesis can be challenging.
- Mild and efficient deoxyfluorination methods are sought after.
Purpose of the Study:
- To explore pentafluoropyridine (PFP) as a reagent for deoxyfluorination of carboxylic acids.
- To develop a one-pot method for amide bond formation using PFP.
- To assess the efficiency and scope of the PFP-mediated reactions.
Main Methods:
- Deoxyfluorination of various carboxylic acids using pentafluoropyridine (PFP).
- In situ generation of acyl fluorides from carboxylic acids.
- One-pot reaction of generated acyl fluorides with amines to form amides.
Main Results:
- Pentafluoropyridine (PFP) effectively converts carboxylic acids into acyl fluorides under mild conditions.
- A range of carboxylic acids were successfully transformed.
- The one-pot deoxyfluorination followed by amidation yielded amides in high yields (up to 94%).
Conclusions:
- Pentafluoropyridine (PFP) is a cost-effective and efficient reagent for deoxyfluorination.
- The developed one-pot method provides straightforward access to amides.
- This approach offers a practical alternative for amide synthesis.
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