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

A method of selectively preparing a chiral 1S, 2S, aryl or heterocyclic sulfonamide, said method comprising the steps of:

• (a) 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;
• (b) reducing the di-tert-butyl 1-(1S,2S)-(1-{[(4S)-4-benzyl-2-oxo-1,3-oxazolidine-3-yl]-carbonyl}-trifluoromethyl-alkyl substituted alkyl)hydrazine-1,2-dicarboxylate of (a) to yield di-tert-butyl 1-(1S,2S)-[trifluoromethyl-alkyl substituted alkyl]hydrazine-1-(hydroxymethyl)-1,2-dicarboxylate;
• (c) deblocking the product of (b) with an acid to yield the acid addition salt of (2S,3S)-trifluoro-hydrazino-methyl alkan-1-ol;
• (d) hydrogenating the acid addition salt of (2S,3S)-trifluor-2-hydrazino-methyl alkan-1-ol in the presence of suitable metal catalyst to yield the amino alcohol (2S,3S)-2-Amino-trifluoro methyl alkan-1-ol HCl;
• (e) triturating the product of (d) in a suitable solvent to remove trapped metal contaminants from the catalyst;
• and
• (f) reacting the amino alcohol or salt thereof with a heterocyclic or aryl-substituted sulfonyl chloride.