Benzyl chloroformate → (2R,3S)-N-carbobenzyloxy-beta-phenyl isoserine methyl ester

HRID 1072942Notes

Reaction equation

HRID 1072942 reaction equation
[CH3:1][O:2][C:3](=[O:14])[C@H:4]([OH:13])[C@H:5]([C:7]1[CH:12]=[CH:11][CH:10]=[CH:9][CH:8]=1)[NH2:6].Cl[C:16]([O:18][CH2:19][C:20]1[CH:25]=[CH:24][CH:23]=[CH:22][CH:21]=1)=[O:17]>N1C=CC=CC=1.CN(C1C=CN=CC=1)C.C(OCC)(=O)C>[CH3:1][O:2][C:3](=[O:14])[C@H:4]([OH:13])[C@H:5]([C:7]1[CH:12]=[CH:11][CH:10]=[CH:9][CH:8]=1)[NH:6][C:16]([O:18][CH2:19][C:20]1[CH:25]=[CH:24][CH:23]=[CH:22][CH:21]=1)=[O:17]

Participants

6

Procedure

A solution of (2R,3S)-β-phenyl isoserine methyl ester (2) (Preparation No. 1, 2 mM) in pyridine containing a small amount of DMAP is cooled in an ice bath and treated with benzyl chloroformate (0.8 ml). After stirring at room temperature overnight, the reaction is diluted with ethyl acetate, washed with 5% aqueous sodium bisulfate, dried and evaporated. The product is obtained pure by silica gel chromatography in ethyl acetate-hexane mixtures. Mp 120-121° C. NMR(CDCl3, TMS): δ 3.26 (m, 1H); 3.79 (s, 3H); 4.47 (m, 1H); 5.06 (m, 2H); 5.27 (d, 1H); 5.75 (m, 1H); 7.20-7.50 (m, 10 H).

Workup

  1. washwashed with 5% aqueous sodium bisulfate
  2. customdried
  3. customevaporated
  4. customThe product is obtained pure by silica gel chromatography in ethyl acetate-hexane mixtures

Sources & evidence

ORD record
ord-2f9dbe92f7f1490f862f9fc257fd589a
Source dataset
uspto-grants-2005_06
Patent number
US06911549B1

Reaction notes

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