Ethanol → ethyl 1-acetyl-2,3-dihydro-5-methoxy-1H-indole-2-carboximidate monohydrochloride
Reaction equation
[C:1]([N:4]1[C:12]2[C:7](=[CH:8][C:9]([O:13][CH3:14])=[CH:10][CH:11]=2)[CH2:6][CH:5]1[C:15]#[N:16])(=[O:3])[CH3:2].[CH2:17]([OH:19])[CH3:18].[ClH:20].C(OCC)C>>[ClH:20].[C:1]([N:4]1[C:12]2[C:7](=[CH:8][C:9]([O:13][CH3:14])=[CH:10][CH:11]=2)[CH2:6][CH:5]1[C:15](=[NH:16])[O:19][CH2:17][CH3:18])(=[O:3])[CH3:2]Participants
4
Procedure
To a solution of intermediate (23) (0.0154 mole) and ethanol (0.0231 mole) in 1M HCl/diethylether (200 ml), cooled in an ice bath was bubbled HCl (gas) for 60 minutes. The ice bath was maintained for 45 minutes, and the mixture was concentrated at room temperature under vacuum to 200 ml of an oily precipitate. The residue was triturated to a brown solid that became an oil after decanting off the diethylether. The residue was washed with diethylether twice, dissolved in methanol, and used without further purification for further synthesis, yielding ethyl 1-acetyl-2,3-dihydro-5-methoxy-1H-indole-2-carboximidate monohydrochloride (intermediate 24).