THE GENERATION OF THE DIISOPROPYL NITROXIDE RADICAL DURING THE REACTION OF LITHIUM DIISOPROPYLAMIDE WITH ALPHA-FLUOROACETATE ESTERS

The formation of an EPR active species was observed when lithium diiso propylamide (LDA) was employed as the base for deprotonation of fluoro acetates. The EPR of a glass prepared from the reaction mixture showed an intense signal. The solution EPR spectrum of the sample was indepe ndent of temperature, and exhibited a hyperfine structure which allowe d identification of the radical species as diisopropyl nitroxide. Gene ration of the enolate by metalation of ethyl fluoroiodoacetate gave no evidence for autoxidation occurring in the absence of diisopropylamin e.