Organocatalytic Aerobic Oxidation of α‐Fluoroalkyl Alcohols to Fluoroalkyl Ketones at Room Temperature

The organocatalytic aerobic oxidation of electron‐deficient α‐fluoroalkyl alcohols at room temperature is described. The resulting fluoroalkyl ketones are versatile synthetic intermediates for a variety of fluorine‐containing molecules. This otherwise difficult transformation has now been accomplished by the reaction of α‐fluoroalkyl alcohols with N ‐oxyl radicals, catalytically generated from 9‐azabicyclo[3.3.1]nonan‐3‐one N ‐oxyl/nitrogen oxide (keto‐ABNO/NO x ) and oxygen in acetic acid (AcOH), affording the corresponding fluoroalkyl ketones in high yield. This operationally simple reaction can be performed under mild conditions, and was applied to a wide range of alcohols (20 examples), thus demonstrating a high functional group tolerance. Moreover, a modified one‐pot protocol based on this method was able to convert an aldehyde to a trifluoromethyl ketone on a gram scale.