Reaktion #87178

Reaktionsgleichung

K2CO3

Boc-L-dopa

benzyl bromide

→

(S)-benzyl 3-(3,4-bis(benzyloxy)phenyl)-2-(tert-butoxycarbonylamino)propanoate

Ausbeute 163.3%

Lösungsmittel

acetonitrile

Reaktionsbedingungen

Aufarbeitung

1. 1
   Temperaturcooled to ambient temperature
2. 2
   FiltrationThe mixture was filtered
3. 3
   Waschenthe filtration cake was washed with acetonitrile (50 mL)
4. 4
   Einengenconcentrated to dryness
5. 5
   SonstigeThe residue was purified by flash column chromatography on silica gel (Hexane/EtOAc=20:1)

Vorschrift

K2CO3 (21.0 g, 150 mmol) was added to a solution of Boc-L-dopa (10.0 g, 33 mmol) in acetonitrile (100 mL) followed by addition of benzyl bromide (21.0 g, 123 mmol). The suspension was heated at 50-60° C. for 4 h and then cooled to ambient temperature. The mixture was filtered and the filtration cake was washed with acetonitrile (50 mL). The filtrate and washings were combined and concentrated to dryness. The residue was purified by flash column chromatography on silica gel (Hexane/EtOAc=20:1) to afford (S)-benzyl 3-(3,4-bis(benzyloxy)phenyl)-2-(tert-butoxycarbonylamino)propanoate (15.3 g, yield 80%).

Quelle