Tetrabutylammonium Fluoride → 2-(1-Methylethyl)-5-nitro-1H-indole

Participants

Reaction Conditions

Reaction Steps

A mixture of methyl 4-(2-butyramido-5-nitrophenyl)-2,2-dimethylbut-3-ynoate (0.50 g, 1.5 mmol) and TBAF (790 mg, 3.0 mmol) in DMF (20 mL) was heated at 70° C. for 24 h. The reaction mixture was cooled to room temperature and poured into ice water. The mixture was extracted with ether (30 mL×3). The combined organic layers were dried over anhydrous Na2SO4 and evaporated under reduced pressure to give a residue, which was purified by column chromatography on silica gel (petroleum ether/ethyl acetate=20/1) to give 2-isopropyl-5-nitro-1H-indole (100 mg, 33%). 1H NMR (400 MHz, CDCl3) δ 8.68 (s, 1 H), 8.25 (br s, 1 H), 8.21 (dd, J=2.4, 10.0 Hz, 1 H), 7.32 (d, J=8.8 Hz, 1 H), 6.41 (s, 1 H), 3.07-3.14 (m, 1 H), 1.39 (d, J =6.8 Hz, 6 H).

Provenance & Evidence