Hydrochloric Acid → 6-Cyclopropyl-8-[(2,6-difluorobenzyl)oxy]-2-methylimidazo[1,2-a]pyridine-3-carboxylic acid
Reaction equation
[CH:1]1([C:4]2[CH:5]=[C:6]([O:19][CH2:20][C:21]3[C:26]([F:27])=[CH:25][CH:24]=[CH:23][C:22]=3[F:28])[C:7]3[N:8]([C:10]([C:14]([O:16]CC)=[O:15])=[C:11]([CH3:13])[N:12]=3)[CH:9]=2)[CH2:3][CH2:2]1.[OH-].[Li+].Cl>O1CCCC1.CO>[CH:1]1([C:4]2[CH:5]=[C:6]([O:19][CH2:20][C:21]3[C:26]([F:27])=[CH:25][CH:24]=[CH:23][C:22]=3[F:28])[C:7]3[N:8]([C:10]([C:14]([OH:16])=[O:15])=[C:11]([CH3:13])[N:12]=3)[CH:9]=2)[CH2:2][CH2:3]1Participants
5
Reactant 3
Product 1
Reagents, catalysts & solvents 1
Conditions
- Temperature
- 40 °C
Procedure
470 mg of ethyl 6-cyclopropyl-8-[(2,6-difluorobenzyl)oxy]-2-methylimidazo[1,2-a]pyridine-3-carboxylate (Example 41A) were initially charged in 36 ml of tetrahydrofuran/methanol 5:1, and 6.1 ml of 1N aqueous lithium hydroxide solution were added. The mixture was stirred at 40° C. for 4 h and then acidified with 6 N hydrochloric acid and concentrated. The residue was taken up in water and repeatedly extracted with dichloromethane. The combined organic phases were washed with saturated aqueous sodium chloride solution, dried with magnesium sulphate and filtered, and the filtrate was concentrated. This gave 470 mg of the desired product (90% pure; 97% of theory) which was reacted without further purification.
Workup
- additionwere added
- concentrationconcentrated
- extractionrepeatedly extracted with dichloromethane
- washThe combined organic phases were washed with saturated aqueous sodium chloride solution
- dry with materialdried with magnesium sulphate
- filtrationfiltered
- concentrationthe filtrate was concentrated
- customThis gave 470 mg of the desired product (90% pure; 97% of theory) which was reacted without further purification
Sources & evidence
- ORD record
- ord-51125c6f1e7a45ecb3054827232c4256
- Source dataset
- uspto-grants-2015_02
- Patent number
- US08946215B2
Reaction notes
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