Sodium Hydroxide → 4-[bis(tert-Butoxy)phosphorylhydroxymethyl]-D,L-phenylalanine
Reaction equation
[C:1]([O:5][P:6]([CH:13]([OH:27])[C:14]1[CH:26]=[CH:25][C:17]([CH2:18][CH:19]([C:21]([O:23]C)=[O:22])[NH2:20])=[CH:16][CH:15]=1)([O:8][C:9]([CH3:12])([CH3:11])[CH3:10])=[O:7])([CH3:4])([CH3:3])[CH3:2].[OH-].[Na+]>O1CCOCC1>[C:9]([O:8][P:6]([CH:13]([OH:27])[C:14]1[CH:26]=[CH:25][C:17]([CH2:18][CH:19]([C:21]([OH:23])=[O:22])[NH2:20])=[CH:16][CH:15]=1)([O:5][C:1]([CH3:3])([CH3:4])[CH3:2])=[O:7])([CH3:10])([CH3:11])[CH3:12]Participants
4
Procedure
A solution of compound 8 (410 mg, 1.02 mmol) in dioxane (10 mL) is treated with 1 N NaOH (5.1 mL, 5 eq.) and stirred at ambient temperature (0.5 h), yielding a solution of crude 4-[bis(tert-Butoxy)phosphorylhydroxymethyl]-D,L-phenylalanine (15), which is not isolated. The pH is adjusted to 8 by bubbling in CO2 gas, Fmoc-OBT (402 mg, 1.12 mmol) is added and the mixture stirred at ambient temperature (3.5 hours). Ice-cold 5% citric acid (25 mL) is added and the resultant solution is extracted with CHCl3 (3×30 mL). The combined extracts are dried (MgSO4) and evaporated under reduced pressure to yield crude 16. Purification by silica gel chromatography affords pure 16 as a colorless foam (277 mg, 44%).
Sources & evidence
- ORD record
- ord-6ccb691e645d44a4b9f63aaef6125e97
- Source dataset
- uspto-grants-1993_11
- Patent number
- US05264607
Reaction notes
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