Production of chirally pure amino alcohol intermediates, derivatives thereof, and uses thereof

A method of selectively preparing a chiral 2S-amino alcohol useful in preparation of an amide sulfonated or acylated with alkyl, substituted aryl or substituted heteroaryl is described. The method involves reacting a di-tert-butyl diazene-1,2-dicarboxylate with a (4S)-4-benzyl-3-[(S)-trifluoromethyl-alkyl substituted alkanoyl]-1,3-oxazolidin-2-one to afford a di-tert-butyl 1-(1S,2S)-([(4S)-4-benzyl-2-oxo-1,3-oxazolidine-3-yl]-carbonyl}-trifluoromethyl-alkyl substituted alkyl)hydrazine-1,2-dicarboxylate. This dicarboxylate is then reduced to yield di-tert-butyl 1-(1S,2S)-[trifluoromethyl-alkyl substituted alkyl]hydrazine-1-(hydroxymethyl)-1,2-dicarboxylate. The resulting product is deblocked with an acid to yield the acid addition salt of (2S,3S)-trifluoro-hydrazino-methyl alkan-1-ol. The acid addition salt of (2S,3S)-trifluoro-2-hydrazino-methyl alkan-1-ol is hydrogenated in the presence of a suitable metal catalyst to yield the amino alcohol (2S,3S)-2-amino-trifluoro-methyl alkan-1-ol HCl.