Acetic Anhydride → Rac.-2-acetamido-3-[4-((1,1-dimethylethoxy)carbonyl]phenyl]propanoic acid benzyl ester
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]=1Participants
5
Reactant 3
Product 1
Reagents, catalysts & solvents 1
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 HCI (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
- washwashed with 1N HCI (2×20 mL), saturated aqueous sodium bicarbonate (2×20 mL)
- dry with materialdried (Na2SO4 )
- filtrationFiltration and concentration
- customprovided the crude product which
- customwas purified by HPLC on silica gel eluting with a mixture of hexanes and ethyl acetate
Sources & evidence
- ORD record
- ord-8ea9cc0b202642a8ac3e37cd473233c3
- Source dataset
- uspto-grants-1994_03
- Patent number
- US05296608
Reaction notes
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