(2R*,3S*)-2-(tert-butoxy-carbonylamino)-3-hydroxy-pentanoate → (3S)-3-Hydroxy-D-norvaline

Participants

Reaction Conditions

Reaction Steps

In a 35 ml microwave vial, the diastereomeric mixture containing ethyl (2R*,3R*) and (2R*,3S*)-2-(tert-butoxy-carbonylamino)-3-hydroxy-pentanoate (0.2 g, 0.81 mmol) was dissolved in a 6.0 M HCl solution (15 mL) and stirred at 130° C. for 30 min. The reaction mixture was concentrated under reduced pressure giving a yellowish solid crude product, as a diastereoisomeric mixture (anti:syn=8:2), which was used without further purification in the following step. MS (ESI) m/z: 134 [M−H]+; (ESI) m/z: 132 [M−H]−. 1H NMR (DMSO-d6) δ 0.92 (t, J=7.36 Hz, 3H), 1.42-1.64 (m, 2H), 3.80 (ddd, J=3.25, 5.80, 11.72 Hz, 1H), 3.86 (d, J=3.02 Hz, 1H), 4.36 (s, 1H), 8.26 (s, 3H) (reported data refer to the major anti diastereoisomer).

Provenance & Evidence