Olah reagent

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The Olah reagent is a nucleophilic fluorinating agent. It consists of a mixture of 70% hydrogen fluoride and 30% pyridine; alcohols react with this reagent to give alkyl fluorides:

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It acts as a stabilized, less volatile form of hydrogen fluoride. It is used in the fluorination of steroids and in deprotection of peptides. [1] [2] [3] Instead of hydrogen fluoride, several other fluorinating agents can be used, such as diethylaminosulfur trifluoride (DAST).

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References

  1. C. G. Bergstrom et al., J. Org. Chem. 28, 2633 (1963)
  2. G. A. Olah et al., Synthesis 1973, 779; idem et al., J. Org. Chem. 44, 3872 (1979).
  3. Review of use in organic synthesis: G. A. Olah et al., J. Fluorine Chem. 33, 377–396 (1986).