The reacion of 3-(trifluoromethyl) benzoic acid (I) first with SOCl2 (or oxalyl chloride) and then with NH4OH in dioxane given the corresponding amide (II), which is treated with SOCl2 giving 3-(trifluoromethyl)benzonitrile (III) was condensed with ethylmagnesium bromide to afford ketone (IV), which was brominated in either methanol or dioxane to yield bromoketone (V). Alkylation of tert-butylamine (VI) with bromoketone (V) provided the aminoketone (VII). Reduction of this ketone to the aminoalcohol was performed with several reagents, among them, borane in THF afforded the most favourable ratio for the desired treo diastereoisomer (80:20). Finally, the diastereomeric mixture was separated by preparative HPLC.