Reaktion #617761

Reaktionsgleichung

(2S*,3R*)-2-amino-3-hydroxy-4,4-dimethyl-pentanoic acid

NaHCO3

(4-phenylphenyl)-methyl-2-pyridyl carbonate

(4-phenylphenyl)-methyl-2-oxopyridine-1-carboxylate

→

title compound

Ausbeute 21.0%

(2S*,3R*)-3-hydroxy-4,4-dimethyl-2-[(4-phenyl-phenyl)-methoxy-carbonylamino]-pentanoic acid

Ausbeute 21.0%

Lösungsmittel

H2O

THF

Reaktionsbedingungen

Aufarbeitung

1. 1
   workup.ADDITIONwas added
2. 2
   Sonstigethe crude mixture was rotary evaporated
3. 3
   Sonstigeto remove the organics and
4. 4
   Extraktionsubsequently extracted with Et2O (3×20 mL)
5. 5
   Extraktionsubsequently extracted with AcOEt (3×20 mL)
6. 6
   TrocknenThe organic fraction was dried over Na2SO4
7. 7
   Filtrationfiltered
8. 8
   Einengenconcentrated to dryness

Vorschrift

To a stirred mixture of (2S*,3R*)-2-amino-3-hydroxy-4,4-dimethyl-pentanoic acid (0.353 g, 2.19 mmol) and NaHCO3 (0.184 g, 0.84 mmol) in H2O (15 mL), at rt, the isomeric mixture containing (4-phenylphenyl)-methyl-2-pyridyl carbonate and (4-phenylphenyl)-methyl-2-oxopyridine-1-carboxylate (0.815 g, 2.2 mmol) [prepared as for example 17, step 1] in THF (15 mL) was added. After 15 h at rt, the crude mixture was rotary evaporated to remove the organics and subsequently extracted with Et2O (3×20 mL). The aqueous phase was acidified with 2.0 M HCl solution to pH 2-3 and subsequently extracted with AcOEt (3×20 mL). The organic fraction was dried over Na2SO4, filtered and concentrated to dryness to afford the title compound (0.181 g, 21%), which was used in the next step without further purification. MS (ESI) m/z: 410 [M−K]+; (ESI) m/z: 370 [M−H]−.

Quelle