1,2-Dibromoethane → 6-(2-bromoethoxy)-N-cyclohexyl-4-methyl-1H-indole-2-carboxamide

Participants

Reaction Conditions

Reaction Steps

To a stirred solution of N-cyclohexyl-6-hydroxy-4-methyl-1H-indole-2-carboxamide (I-9A-b: 0.7 g, 2.57 mmol) in acetonitrile (20 mL) was added Cs2CO3 (1.67 g, 5.14 mmol) cooled to 0° C. followed by 1,2-dibromoethane (1.1 mL, 12.86 mmol) dropwise. The reaction mixture was stirred at room temperature for 16 h, diluted with water (20 mL) and extracted with ethyl acetate (2×100 mL). The combined ethyl acetate layers were washed with brine (100 mL), dried over anhydrous Na2SO4 and concentrated under reduced pressure. The crude compound was purified by column chromatography over silica gel (100-200 mesh) using a solvent gradient of 50% ethyl acetate in petroleum ether as eluent to afford 200 mg (21%) of 6-(2-bromoethoxy)-N-cyclohexyl-4-methyl-1H-indole-2-carboxamide (I-9A-c) as an off-white solid.

Provenance & Evidence