1,1'-Carbonyldiimidazole → methyl 4-bromo-2-{[(5-methoxy-2-methyl-1H-indol-3-yl)acetyl]amino}benzoate

Beteiligte Stoffe

Reaktionsschritte

5-Methoxy-2-methyl-3-indole acetic acid (5 g, obtainable from Acros), carbonyidiimidazole (4.44 g) and tetrahydrofuran (120 ml) were stirred at room temperature for 30 min after which methyl 4-bromoanthranilate (5.24 g) and pyridinium tosylate (13.69 g) were added and the mixture refluxed for 14 h. After diluting with dichloromethane (200 ml), the residue was washed with 2M hydrochloric acid (200 ml), 2M sodium hydroxide (200 ml), water (200 ml) and brine (200 ml) and dried (MgSO4). After solidifying by treatment with cyclohexane and ethyl acetate, the solid was triturated with ether to afford methyl 4-bromo-2-{[(5-methoxy-2-methyl-1H-indol-3-yl)acetyl]amino}benzoate (6.54 g), MH+ 433, 435; MH− 431, 433; TR 3.67 min.

Herkunft & Nachweise