[OH:1][C:2]([C@H:5]1[CH2:9][O:8]C(C)(C)[N:6]1C(OC(C)(C)C)=O)([CH3:4])[CH3:3].[ClH:19]>C(O)C>[ClH:19].[NH2:6][C@@H:5]([C:2]([CH3:4])([OH:1])[CH3:3])[CH2:9][OH:8]tert-Butyl (4R)-4-(1-hydroxy-1-methylethyl)-2,2-dimethyl-1,3-oxazolidine-3-carboxylate (7.32 g, 27.8 mmol), prepared by the method of Joullie, Tetrahedron, 52, pp. 11673-11694, (1996), was dissolved in 20 mL of ethanol. A 4.3 M solution of hydrochloric acid in ethanol (15 mL) was then added and the reaction mixture was heated 85° C. After 2 hours, the solution was cooled and concentrated under reduced pressure. The resulting residue was concentrated with 2-propanol several times and then with Et2O to give crude (2R)-2-amino-3-methylbutane-1,3-diol hydrochloride (4.32 g) as a brown oil. This was used in the next reaction without further purification.
Wird geladen…
