Acetic Anhydride → Rac.-2-acetamido-3-[4-((1,1-dimethylethoxy)carbonyl]phenyl]propanoic acid benzyl ester

HRID 1721236Notes

Reaction equation

HRID 1721236 reaction equation
[C:1](OC(=O)C)(=[O:3])[CH3:2].C(N(CC)CC)C.C1(C)C=CC(S(O)(=O)=O)=CC=1.[CH2:26]([O:33][C:34](=[O:51])[CH:35]([NH2:50])[CH2:36][C:37]1[CH:42]=[CH:41][C:40]([C:43]([O:45][C:46]([CH3:49])([CH3:48])[CH3:47])=[O:44])=[CH:39][CH:38]=1)[C:27]1[CH:32]=[CH:31][CH:30]=[CH:29][CH:28]=1>ClCCl>[CH2:26]([O:33][C:34](=[O:51])[CH:35]([NH:50][C:1](=[O:3])[CH3:2])[CH2:36][C:37]1[CH:38]=[CH:39][C:40]([C:43]([O:45][C:46]([CH3:48])([CH3:47])[CH3:49])=[O:44])=[CH:41][CH:42]=1)[C:27]1[CH:32]=[CH:31][CH:30]=[CH:29][CH:28]=1

Participants

5

Reactant 3

HCID 7918Acetic AnhydrideHCID 8471TriethylamineHCID 86746526Rac.-2-amino-3-[4-[(1,1-dimethylethoxy)carbonyl]phenyl]propanoic acid benzyl ester p-toluenesulfonic acid salt

Product 1

HCID 14888682Rac.-2-acetamido-3-[4-((1,1-dimethylethoxy)carbonyl]phenyl]propanoic acid benzyl esterYield 91%

Reagents, catalysts & solvents 1

HCID 6344DichloromethaneSolvent2×

Procedure

Acetic anhydride (1.0 mL, 10.8 mmol) and triethylamine (2.4 g, 24 mmol) were added sequentially to a solution of rac.-2-amino-3-[4-[(1,1-dimethylethoxy)carbonyl]phenyl]propanoic acid benzyl ester p-toluenesulfonic acid salt (5.0 g, 9 mmol) in dichloromethane (100 ml) at 0° C. After 2 h, the reaction mixture was diluted with dichloromethane (250 mL) and washed with 1N HCl (2×20 mL), saturated aqueous sodium bicarbonate (2×20 mL) and dried (Na2SO4). Filtration and concentration provided the crude product which was purified by HPLC on silica gel eluting with a mixture of hexanes and ethyl acetate to give rac.-2-acetamido-3-[4-[(1,1-dimethylethoxy)carbonyl]phenyl]propanoic acid benzyl ester (3.3 g, 8 mmol) in 91% yield.

Workup

  1. washwashed with 1N HCl (2×20 mL), saturated aqueous sodium bicarbonate (2×20 mL)
  2. dry with materialdried (Na2SO4)
  3. filtrationFiltration and concentration
  4. customprovided the crude product which
  5. customwas purified by HPLC on silica gel eluting with a mixture of hexanes and ethyl acetate

Sources & evidence

ORD record
ord-38b5dc4d9f82457a9250dacb9623a94f
Source dataset
uspto-grants-1996_04
Patent number
US05508437

Reaction notes

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