The method of synthesizing chirally pure β- amino alcohol

To provide a process for the preparation of the S enantiomer of chirally pure α- amino acids comprising the following steps: a) reacting a compound of formula Obtaining a carboxylic acid b) an organic metal reagent is added to carbon dioxide; c) a tertiary presence an acid chloride of an amine base, phosphorus trichloride, acid anhydride, or activated carboxylic acid by thionyl chloride process; Reacting an alkali metal salt of the product and S-4-benzyl-2-oxazolidinone d) step c); Step of forming the enolate anion by treating the product of step e) d) a non-nucleophilic strong base; Obtaining a oxazolidinone azide trap f) enolate anion with 2,4,6-triisopropyl benzenesulfonyl azide; g) and the oxazolidinone azide is hydrolyzed with aqueous base to obtain the α- azido acid; Step reducing h) alpha-azido acid to alpha-amino acids and, i) alpha-amino acids were recrystallized to obtain a chirally pure alpha-amino acids. Further provides a process for the preparation of the S enantiomer of chirally pure β- amino alcohol, the method further the step and β- amino alcohol of reducing crude α- amino acid into β- amino alcohol by recrystallization It comprises obtaining the chirally pure β- amino alcohol. Furthermore, also provides a process for the preparation of the S enantiomer of chirally pure N- sulfonyl β- amino alcohol, the method further β- amino alcohol 5-chloro - sulfonylation with thiophene-2-sulfonyl halide process; and recrystallized comprises obtaining the chirally pure N- sulfonyl β- amino alcohol.