Lithium Hydroxide → 4-Cyano-5-methyl-1H-pyrrole-2-carboxylic acid
Reaction equation
[OH-].[Li+].[C:3]([C:5]1[CH:6]=[C:7]([C:11]([O:13]CC)=[O:12])[NH:8][C:9]=1[CH3:10])#[N:4]>CO>[C:3]([C:5]1[CH:6]=[C:7]([C:11]([OH:13])=[O:12])[NH:8][C:9]=1[CH3:10])#[N:4]Participants
4
Reactant 2
Product 1
Reagents, catalysts & solvents 1
Conditions
- Temperature
- 90 °C
Procedure
Lithium hydroxide (2 N, 2 ml) was warmed to 40° C. and a solution of ethyl 4-cyano-5-methyl-1H-pyrrole-2-carboxylate (Intermediate 14, 0.16 g) in 2 ml of MeOH was added. The reaction temperature was gradually increased to 90° C. and the reaction was stirred at that temperature for 2 hours. Then MeOH was removed and the remaining aqueous solution was cooled to 0° C. and acidified with 3 M HCl (pH ˜2). The acidic solution was extracted with EtOAc, the combined organic extracts were dried over magnesium sulfate and concentrated to give brown solid (0.07 g, crude).
Workup
- customThen MeOH was removed
- temperaturethe remaining aqueous solution was cooled to 0° C.
- extractionThe acidic solution was extracted with EtOAc
- dry with materialthe combined organic extracts were dried over magnesium sulfate
- concentrationconcentrated
- customto give brown solid (0.07 g, crude)
Sources & evidence
- ORD record
- ord-7594a4d07d7740ce83abc641d23f7e13
- Source dataset
- uspto-grants-2010_05
- Patent number
- US07709503B2
Reaction notes
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