Fluoroalkylamine reagents mechanism

A possible mechanism for the fluorination reaction of alcohols with fluoroalkylamine reagents is shown for reagent 2. " ... 

The fluoroalkylamine reagent (FAR) 2-chloro-l,l,2-trifluorotriethylamine gives alkyl fluorides from alcohols in one step and is known as the Yarovenko reagent." This reagent is less reactive than DAST but was used intensively before the introduction of DAST. Rearrangement and elimination are similar with FAR and DAST (equations 39 and 40).This may be explained by the similar mechanism. Activation of the alcohol by intermediate formation of ester-type derivatives is followed by SN2-type displacement by fluoride ion (Scheme 32). 

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