A Convenient, One-Pot Procedure for the Preparation of Acyl and Sulfonyl Fluorides Using Cl3CCN, Ph3P, and TBAF(t-BuOH)4

Various carboxylic acids were converted into acyl fluorides in excellent yields by treatment with trichloroacetonitrile, triphenylphosphine, and TBAF(t-BuOH)4 at room temperature. The reaction was applicable to the preparation of acid-sensitive amino acid fluorides without deprotection or rearrangement.