Amine hydrofluorides reactions with epoxides

Table 17 indicates some limitations of the amine hydrofluorides in the reaction with glycidic esters. In the least-substituted case (entry 1) the yield is low. On the other hand, the fully substituted glycidic esters (entries 8 and 9) do not react at all with the amine hydrofluoride, probably due to steric hindrance. This type of epoxide gives better results with other fluorination reagents, e.g. they can be opened to the fluorohydrins in good yield with hydrogen fluoride in the presence of the boron trifluoride-diethyl ether complex (sec Section 1.1.4.3.2.1.2.).37... 

Similar results, with even higher regiosclectivities than wdih diisopropylaminc trishydrofluoride. arc reported for the reaction of simple epoxides with Hiinig s hydrofluoride" (i.e., the 1 1 adduct ofA .A-diisopropylethylamine and hydrogen fluoride, which in turn is prepared ill situ by the addition of the appropriate amount of amine to the amine trishydrofluoride). ... 

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