863094-23-9Relevant articles and documents
PROCESS FOR THE PREPARATION OF ENANTIOMERICALLY PURE 1-SUBSTITUTED-3-AMINOALCOHOLS
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Page/Page column 20-22, (2008/06/13)
Provided is a process for the preparation of N-monosubstituted β-aminoalcohol sulfonates of formula (Ia), (Ib) wherein R1 is C6-20 aryl or C4-12 heteroaryl, each optionally being substituted with one or more halogen atoms and/or one or more C1-4 alkyl or C1-4 alkoxy groups, R2 is C1-4-alkyl or C6-20 aryl, each aryl optionally being substituted with one or more halogen atoms and/or one or more C1-4-alkyl or C1-4-alkoxy groups, and wherein R3 is selected from the group consisting of C1-18 alkyl, C6-20 cycloalkyl, C6-20 aryl and C7-20 aralkyl residues, comprising the steps of a) reacting a methyl ketone, a primary amine, formaldehyde and a sulfonic acid, at a pressure above 1.5 bar, optionally in a organic solvent, said organic solvent optionally containing water, to afford N-monosubstituted β-aminoketone sulfonates of formula (II), wherein R1, R2 and R3 are as defined above, and b) asymmetrically hydrogenating said sulfonates in the presence of a base and a catalyst, comprising a transition metal and a diphosphine ligand, in a polar solvent, optionally in the presence of water.
