Cesium carbonate → Methyl 1-(cinnolin-4-yl)-1H-indole-3-carboxylate

Participants

Reaction Conditions

Reaction Steps

1 mmol (175 mg) of 1H-indole-3-carboxylic acid methyl ester, 1.1 mmol (181 mg) of 4-chloro-cinnoline and 1.2 mmol (390 mg) of Cs2CO3 are suspended in 3 ml of dry DMF. The mixture is stirred for 60 h at 80° C. under argon, allowed to cool to room temperature, and diluted with water (20 ml). Part of the product precipitates and is filtered off, the filtrate is extracted twice with ethyl acetate (20 ml portions). The combined extracts are dried over anhydrous Na2SO4 and evaporated. The residue is combined with the precipitate and purified by prep. HPLC to yield 1-(cinnolin-4-yl)-1H-indole-3-carboxylic acid methyl ester (MS molpeak 304 (M+H, electrospray ionization)) as an off-white foam after freeze-drying.

Provenance & Evidence