Hydrochloric Acid → Boc-4-bromo-D-phenylalanine methyl ester

HRID 2384098Notes

Reaction equation

HRID 2384098 reaction equation
[Br:1][C:2]1[CH:7]=[CH:6][C:5]([CH2:8][C@@H:9]([NH:13][C:14]([O:16][C:17]([CH3:20])([CH3:19])[CH3:18])=[O:15])[C:10]([OH:12])=[O:11])=[CH:4][CH:3]=1.[C:21]([O-])([O-])=O.[Cs+].[Cs+].IC.Cl>CN(C=O)C>[CH3:21][O:11][C:10](=[O:12])[C@H:9]([NH:13][C:14]([O:16][C:17]([CH3:20])([CH3:19])[CH3:18])=[O:15])[CH2:8][C:5]1[CH:4]=[CH:3][C:2]([Br:1])=[CH:7][CH:6]=1

Participants

6

Reactant 4

HCID 313Hydrochloric AcidHCID 6328Methyl iodideHCID 10796Cesium carbonateHCID 7020327(2R)-3-(4-bromophenyl)-2-{[(tert-butoxy)carbonyl]amino}propanoic acid

Product 1

HCID 15735974Boc-4-bromo-D-phenylalanine methyl ester

Reagents, catalysts & solvents 1

HCID 6228DimethylformamideSolvent

Procedure

To a solution of (R)-3-(4-Bromo-phenyl)-2-tert-butoxycarbonylamino-propionic acid (1.0 g, 2.91 mmol) in DMF (5 mL) is added Cs2CO3 (1.041 g, 3.2 mmol) and the mixture is stirred at room temperature for 30 minutes. Then iodomethane (1.031 g, 7.26 mmol) is added and the mixture is stirred at room temperature about 72 hours. The pH is adjusted to 5˜6 by adding 1N HCl then the mixture is extracted with EtOAc. The combined organic layers were washed with water and brine, dried over MgSO4, filtered and concentrated to give (R)-3-(4-bromo-phenyl)-2-tert-butoxycarbonylamino-propionic acid methyl ester. HPLC Retention time 1.49 minutes (condition C): MS 358.3 (M−1).

Workup

  1. stirringthe mixture is stirred at room temperature about 72 hours
  2. extractionthe mixture is extracted with EtOAc
  3. washThe combined organic layers were washed with water and brine
  4. dry with materialdried over MgSO4
  5. filtrationfiltered
  6. concentrationconcentrated

Sources & evidence

ORD record
ord-6513398085fa4dfc90941c9b790702d5
Source dataset
uspto-grants-2012_09
Patent number
US08263629B2

Reaction notes

Loading…