1,4-Dioxane → 1-methyl-3-(4-nitro-phenylmethyl)-1H-indole-5-carboxylic acid methyl ester

Participants

Reaction Steps

A solution of 1-methyl-1H-indole-5-carboxylic acid methyl ester (0.38 g, 2.0 mmol), prepared using procedures as described in Example 1, Ag2O (0.51 g, 2.2 mmol), 4-nitro-benzyl bromide (0.48 g, 2.2 mmol) and dioxane (6 mL) was heated to reflux for 25 hr, then more 4-nitro-benzyl bromide (0.48 g, 2.2 mmol) was added and the solution was heated at reflux an additional 4 days. After cooling to room temperature, the reaction mixture was diluted with ether (50 mL) and ethyl acetate (50 mL), washed with aq. NH4Cl (50 mL) and then brine (50 mL). The organic layer was dried over MgSO4, filtered and concentrated. The remaining residue was subjected to flash chromatography (ethyl acetate/hexane, 1:4) to provide of 1-methyl-3-(4-nitro-phenylmethyl)-1H-indole-5-carboxylic acid methyl ester (0.38 g, 58% yield). 1H NMR (400 MHz, CDCl3) δ 8.26 (s, 1H), 8.16 (d, 2H, J=8.3 Hz), 7.98 (d, 1H, J=8.3 Hz), 7.45 (d, 2H, J=8.3 Hz), 7.35 (d, 1H, J=8.3 Hz), 6.90 (s, 1H), 4.25 (s, 2H), 3.94 (s, 3H), 3.82 (s, 3H).

Provenance & Evidence