Tetrabutylammonium Fluoride → tert-Butyl [3-nitro-1H-indol-4-yl]acetate
Reaction equation
[N+:1]([C:4]1[C:12]2[C:7](=[CH:8][CH:9]=[CH:10][C:11]=2[CH2:13][C:14]([O:16][C:17]([CH3:20])([CH3:19])[CH3:18])=[O:15])[N:6](S(C2C=CC=CC=2)(=O)=O)[CH:5]=1)([O-:3])=[O:2].[F-].C([N+](CCCC)(CCCC)CCCC)CCC>C1COCC1>[N+:1]([C:4]1[C:12]2[C:7](=[CH:8][CH:9]=[CH:10][C:11]=2[CH2:13][C:14]([O:16][C:17]([CH3:20])([CH3:19])[CH3:18])=[O:15])[NH:6][CH:5]=1)([O-:3])=[O:2]Participants
4
Reactant 2
Product 1
Reagents, catalysts & solvents 1
Procedure
To a solution of tert-butyl [3-nitro-1-(phenylsulfonyl)-1H-indol-4-yl]acetate from Step C (730 mg, 1.75 mmol) in THF (5 mL) was added tetrabutylammonium fluoride (1.0 M in THF, 5.25 mL, 5.25 mmol) and the reaction mixture was stirred at ambient temperature for 10 min, then concentrated in vacuo. The residue was partitioned between saturated aqueous NaHCO3 (5 mL) and extracted with CHCl3 (15 mL). The organic extract was dried over Na2SO4, filtered, and concentrated in vacuo. The crude product was purified by silica gel chromatography, eluting with a gradient of CHCl3:EtOAc—90:10 to 50:50, to give the title compound. MS: m/z=221 (M−C4H7).