3-Methylbutanal → 5-bromo-3-isopropyl-1H-indole

Participants

Reaction Conditions

Reaction Steps

3-Methylbutanal (0.921 g, 10.69 mmol) was added to a solution of (4-bromophenyl)hydrazine (2 g, 10.69 mmol) in acetic acid (100 mL) at 80° C., and the mixture was stirred for 3 h at 120° C. The reaction mixture was concentrated to get the residue, and the residue was partitioned between ethyl acetate and water. Organic layer was separated, washed with saturated bicarbonate solution and brine, dried over sodium sulphate and filtered. The filtrate was concentrated in vacuo and purified by flash chromatography using 2% ethyl acetate in pet ether to afford title compound (1.1 g, 38.4%) as an oil. 1H NMR (400 MHz, CDCl3): δ 7.91 (bs, 1H), 7.76 (m, 1H), 7.25-7.20 (m, 2H), 6.95 (d, J=2.4 Hz, 1H), 3.18-3.11 (m, 1H), 1.35 (d, J=6.8 Hz, 6H).

Provenance & Evidence