Acetic Acid → US10442803, Example 2a
Reaction equation
[CH3:1][C:2]1[N:10]([S:11]([C:14]2[CH:19]=[CH:18][CH:17]=[CH:16][CH:15]=2)(=[O:13])=[O:12])[C:9]2[C:4](=[N:5][C:6]([N:20](C(OC(C)(C)C)=O)[NH:21][C:22](OC(C)(C)C)=O)=[CH:7][CH:8]=2)[CH:3]=1.[C:36](O)(=O)C>>[CH3:36][C:22]1[N:5]2[C:4]3[CH:3]=[C:2]([CH3:1])[N:10]([S:11]([C:14]4[CH:15]=[CH:16][CH:17]=[CH:18][CH:19]=4)(=[O:12])=[O:13])[C:9]=3[CH:8]=[CH:7][C:6]2=[N:20][N:21]=1Participants
Conditions
- Temperature
- 120 °C
Procedure
A mixture of di-tert-butyl 1-[2-methyl-1-(phenylsulfonyl)-1H-pyrrolo[3,2-b]pyridin-5-yl]hydrazine-1,2-dicarboxylate (19.53 g, 38.86 mmol, from Step 3) in acetic acid (200 mL) was heated at 120° C. overnight. Precipitate was filtered off, and the filtrate was concentrated in vacuo. Dichloroethane (15 mL) was added, and the suspension was heated at reflux for 15 minutes. Upon cooling to 0° C., the solid product was isolated by filtration and dried at 40° C. under vacuum to give an off-white solid (5.94 g). Solvent was removed from the filtrate in vacuo and the above procedure was repeated using DCE (6 mL) to afford additional solid (3.6 g). Additional product was obtained by flash chromatography of the filtrate, (eluting with a gradient of 0-1% MeOH/DCM containing 1% NH4OH). The chromatography afforded product as a glass, which was recrystallized from MeOH (6 mL). Upon recrystallization, product was isolated as white crystals and air dried (2.19 g). Yield: (11.7 g, 92%).
Workup
- filtrationPrecipitate was filtered off
- concentrationthe filtrate was concentrated in vacuo
- additionDichloroethane (15 mL) was added
- temperaturethe suspension was heated
- temperatureat reflux for 15 minutes
- temperatureUpon cooling to 0° C.
- customthe solid product was isolated by filtration
- customdried at 40° C. under vacuum
Sources & evidence
- ORD record
- ord-41f98568e5d147bb903c093b1fbf6fad
- Source dataset
- uspto-grants-2016_04
- Patent number
- US09309246B2
Reaction notes
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