Analogues of Key Precursors of Aspartyl Protease Inhibitors: Synthesis of Trifluoromethyl Amino Epoxides

The synthesis of the title compound is described through
original and tailored synthetic protocols. The addition of
vinylmagnesium bromide to CF3-N-aryl and N-alkyl aldimines was efficient and did not require an activating
N-substituent. The resultant CF3-allylamines were converted in an efficient and completely stereoselective route
to syn CF3-epoxides 3 via formation of bromhydrins 8. The
same sequence performed from the aldimine substituted
with the methyl ether of the (R)-phenylglycinol provided the
homochiral (R,R)-amino epoxide (de >98%). This study has
allowed access to the novel racemic and homochiral trifluoromethyl β-amino epoxides, analogues of key precursors of
various HIV protease inhibitors.