Methods of preparing a fluorinated aryl or heteroaryl substrate by combining a quaternary ammonium cyanide and an aryl or heteroaryl substrate substituted with at least one chloro, bromo, sulfonyl, or nitro group to thereby provide a mixture, and combining the mixture with hexafluorobenzene to thereby provide the fluorinated substrate.
Mild Fluorination of Chloropyridines with in Situ Generated Anhydrous Tetrabutylammonium Fluoride
作者:Laura J. Allen、Joseck M. Muhuhi、Douglas C. Bland、Rachel Merzel、Melanie S. Sanford
DOI:10.1021/jo5003054
日期:2014.6.20
This paper describes the fluorination of nitrogen heterocycles usinganhydrous NBu4F. Quinoline derivatives as well as a number of 3- and 5-substituted pyridines undergo high-yielding fluorination at room temperature using this reagent. These results with anhydrous NBu4F compare favorably to traditional halex fluorinationsusing alkali metal fluorides, which generally require temperatures of ≥100 °C