In order to probe the mechanism of this transformation, epoxysilanes 1-3 were prepared in enantioenriched form by Shi epoxidation of the corresponding allylsilanes (Scheme 3). Like we observed for the racemic sequence, when using allyltriphenylsilane the Shi epoxidation was slower than the other differently substituted allylsilanes. Nonetheless, good yields of triphenylsilyl epoxide 5 could be achieved using a slightly more concentrated reaction mixture and extended reaction times. A comparison of the measured optical activity for triisopropyl silyl epoxide 1 with that previously reported, indicated 1 was obtained as a 62:38 mixture of enantiomers (22% ee), in line with previously obtained values for the same transformation. Treatment of 1-3 with HF•Et3N followed by esterification with (S)-methoxy-α-(trifluoromethyl)phenylacetic acid (4) allowed for an assessment of fluorohydrin enantiopurity by 1 H NMR analysis. In this way, the enantiopurity of all three silyl fluorohydrins was determined to be ~1.5:1, indicating the enantiopurity of the starting epoxide was retained and epoxide opening occurred via an SN2-type process. (e.g. room temperature within one hour) and higher regioselectivity that we attribute to a betasilyl effect. Reactions tended to be slower with phenyl-substituted silanes, which could be due to the electron-withdrawing nature of this group. Extended reaction times, however, allowed for these products to be successfully obtained in similarly high yield to other 3-silylfluorohydrins with differing substituents on silicon. Volatility of some intermediate epoxysilanes prompted us to investigate a one-pot epoxidation/epoxide opening reaction using a combination of mCPBA and HF•Et3N. Yields for this one-pot procedure were generally in the same range as the overall yield from a two-step process involving epoxidation with in situ generated oxone followed by treatment with HF•Et3N. However, the use of mCPBA generally gave small amounts of the 3chlorobenzoate adduct resulting from 3-chlorobenzoic acid epoxide opening. For this reason, our preferred method for substrates with suitably low volatility remains the two-step sequence. Our efforts are currently focused on further transformations of these compounds to access valuable fluorine-and/or silicon-containing synthetic intermediates.