Sodium Hydroxide → 5-Nitroindole-2-carboxylic acid
Reaction equation
C([C:3]1[C:11]2[C:6](=[CH:7][CH:8]=[C:9]([N+:12]([O-:14])=[O:13])[CH:10]=2)[NH:5][C:4]=1[C:15]([OH:17])=[O:16])C.[OH-].[Na+]>C(O)C>[N+:12]([C:9]1[CH:10]=[C:11]2[C:6](=[CH:7][CH:8]=1)[NH:5][C:4]([C:15]([OH:17])=[O:16])=[CH:3]2)([O-:14])=[O:13]Participants
4
Reactant 2
Product 1
Reagents, catalysts & solvents 1
Conditions
- Temperature
- 60 °C
Procedure
To a solution of commercial ethyl 5-Nitro-2-carboxy-indole (10.21 g, 43.6 mmol) in ethanol (220 mL) was added 110 mL of 2 M NaOH. The reaction was stirred at 60° C. for 18 hours. The reaction was then cooled and the ethanol removed in vacuo and then an additional 200 mL water was added. To the vigourously stirring aqueous solution was added 5 M HCl followed by 1 M HCl until pH 4 was attained and the acid product was precipitated. The product was collected by filtration on a Buchner funnel and washed once with dilute HCl (1:40 v/v) and twice with water. The filtrate was dried over P2O5 in a dessicator in vacuo to afford 8.83 g (42.8, 98%) of acid 97.