A process for the preparation of N-monosubstituted β-aminoalcohol sulfonates of formula (1a), (1b): 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; including 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 which can include water to provide N-monosubstituted β-aminoketone sulfonates of formula (II): wherein R1, R2 and R3 are as defined above, and b) asymmetrically hydrogenating.