Lithium borohydride → 7-(1-Methylethyl)-1H-indole
Reaction equation
[CH:1]([C:4]1[CH:5]=[CH:6][CH:7]=[C:8]2[C:12]=1[NH:11][C:10](=O)[C:9]2=O)([CH3:3])[CH3:2].[BH4-].[Li+]>O1CCCC1>[CH:1]([C:4]1[CH:5]=[CH:6][CH:7]=[C:8]2[C:12]=1[NH:11][CH:10]=[CH:9]2)([CH3:3])[CH3:2]Participants
Reactant 2
Product 1
Reagents, catalysts & solvents 1
Conditions
- Temperature
- 90 °C
Procedure
To a solution of 7-isopropyl-1H-indole-2,3-dione (2.97 g, 15.7 mmol) in tetrahydrofuran (20 mL) was dropped 2.0 M solution of lithium borohydride in tetrahydrofuran (15 mL, 30 mmol). The mixture was heated at 90° C. for 4 hours. It was quenched with 5% HCl, followed by saturated sodium bicarbonate. It was extracted with ethyl acetate. The extracts were dried over magnesium sulfate and evaporated to dryness to provide a crude 7-isopropyl-1H-indole. To a solution of the crude 7-isopropyl-1H-indole in diethyl ether (40 mL) was dropped 2.0 M solution of oxalyl chloride in dichloromethane (15 mL, 30 mmol). After stirring at room temperature for 5 hours, it was evaporated to dryness. Ethanol was added to the residue and it was stirred at room temperature overnight. After the ethanol was evaporated, flash chromatography on silica gel provided 0.972 g (24%) of the title compound as solid. ESI (−) MS m/e=258 (MH−).
Workup
- customIt was quenched with 5% HCl
- extractionIt was extracted with ethyl acetate
- dry with materialThe extracts were dried over magnesium sulfate
- customevaporated to dryness
Sources & evidence
- ORD record
- ord-3185225653ea4395934a36d2ac5c9980
- Source dataset
- uspto-grants-2008_11
- Patent number
- US07446122B2
Reaction notes
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