Patent ID: 8344182

Claim:
A process for the preparing (S)-2-amino-1-propanol comprising: 1) reacting (S)-1-methoxy-2-propylamine with at least 2 equivalents of a 30 to 40% strength by weight hydrochloric acid, either Ia) at a temperature greater than 80° C. in an autoclave at a pressure of 3 to 45 bar for 1 to 12 hours and subsequently cooling to room temperature and decompressing of the autoclave or Ib) at reflux for 30 to 60 hours at atmospheric pressure; 2) distilling off aqueous solvent to provide a first intermediate product; 3) then either IIIa) admixing the first intermediate product with an inorganic base to a pH greater than 10, to provide a second intermediate product, or IIIb) reacting the first intermediate product with a mixture of a relatively high-boiling solvent and a relatively strong base; 4) then either IVa) freeing the second intermediate product of IIIa) from water by distillation to provide a residue, admixing the residue with a solvent, and then filtering to give a filtrate, or IVb) mixing the second intermediate product of IIIa) with a mixture of an azeotrope-forming organic solvent and a relatively high-boiling diluent, to form an azeotropic mixture and azeotropically distilling off water and (S)-2-aminopropan-1-ol together with the azeotrope-forming organic solvent to separate at least one (S)-2-aminopropan-1-ol comprising distillation fraction from the azeotropic mixture, then, if the at least one (S)-2-aminopropan-1-ol-comprising distillation fraction comprises two or more distillation fractions, combining the two or more distillation fractions together to give a combined distillate; 5) distilling the filtrate obtained from IVa), a (S)-2-aminopropan-1-ol-comprising distillation fraction or the combined distillate obtained from IVb), or the mixture obtained from IIIb).