Tetrahydrofuran → 3-[5-(Ethoxycarbonyl)-2-formyl-4-methyl-1H-pyrrol-3-yl]propanoic acid
Reaction equation
[CH2:1]([O:3][C:4]([C:6]1[NH:7][C:8]([CH3:17])=[C:9]([CH2:12][CH2:13][C:14]([OH:16])=[O:15])[C:10]=1[CH3:11])=[O:5])[CH3:2].[O:18]1CCCC1>C(O)(=O)C.O.[Cl-].[Na+].O>[CH2:1]([O:3][C:4]([C:6]1[NH:7][C:8]([CH:17]=[O:18])=[C:9]([CH2:12][CH2:13][C:14]([OH:16])=[O:15])[C:10]=1[CH3:11])=[O:5])[CH3:2]Participants
Reactant 2
Product 1
Reagents, catalysts & solvents 3
Conditions
- Temperature
- 5 °C
Procedure
To a mixture of 7 g 4-(2-carboxyethyl)-3,5-dimethyl-1H-pyrrole-2-carboxylic acid ethyl ester in 35 mL each of tetrahydrofuran (THF), acetic acid (AcOH) and water at −10° C. was added 70 g of ceric ammonium nitrate in portion over 20 minutes, the reaction temperature being maintained at about 5° C. The resulting mixture was them cooled to 0° C., stirred for another 2 hr and then diluted with 250 mL of brine. The mixture was then extracted with 2×300 mL 10% MeOH in dichloromethane (DCM). The organic extracts were combined and dried over anhydrous magnesium sulfate (MgSO4), filtered and concentrated. The residue was purified on silica gel column with hexanes(hex)/ethyl acetate (EtOAc)/AcOH (6:4:0.05) followed by crystallization in EtOAc to give 1.5 g of 4-(2-carboxyethyl)-5-formyl-3-methyl-1H-pyrrole-2-carboxylic acid ethyl ester as a white solid.
Workup
- temperaturecooled to 0° C.
- extractionThe mixture was then extracted with 2×300 mL 10% MeOH in dichloromethane (DCM)
- dry with materialdried over anhydrous magnesium sulfate (MgSO4)
- filtrationfiltered
- concentrationconcentrated
- customThe residue was purified on silica gel column with hexanes(hex)/ethyl acetate (EtOAc)/AcOH (6:4:0.05)
- customfollowed by crystallization in EtOAc
Sources & evidence
- ORD record
- ord-c1de0ff2b66b4a70bea99af22c3f807f
- Source dataset
- uspto-grants-2005_02
- Patent number
- US06855730B2
Reaction notes
Loading…