Cesium carbonate → 2-tert-butyl-1-(2-hydroxyethyl)-5-nitro-1H-indole-4-carbonitrile

Participants

Reaction Conditions

Reaction Steps

A mixture of 2-tert-butyl-5-nitro-1H-indole-4-carbonitrile (200 mg, 0.82 mmol), 2-iodoethanol (77 μL, 0.98 mmol), cesium carbonate (534 mg, 1.64 mmol) and DMF (1.3 mL) was heated to 90° C. overnight. Then more 2-iodoethanol (77 μL, 0.98 mmol) was added and the reaction was stirred at 90° C. for 3 days. The reaction mixture was partitioned between ethyl acetate and water. The aqueous layer was washed with ethyl acetate and then the combined ethyl acetate layers were washed with water (×3) and brine, dried over MgSO4 and concentrated. The residue was purified by column chromatography (50-100% CH2Cl2—Hexanes) to yield the product as a yellow solid (180 mg, ˜25% purity by NMR, product co-elutes with the indole starting material). ESI-MS m/z calc. 287.1, found 288.5 (M+1)+. Retention time 1.59 minutes. 1H NMR (400 MHz, DMSO-d6) δ 12.23 (s, 1H), 8.14 (d, J=9.1 Hz, 1H), 8.02 (d, J=9.1 Hz, 1H), 6.60 (s, 1H), 5.10 (t, J=5.5 Hz, 1H), 4.55 (t, J=6.3 Hz, 2H), 3.78-3.73 (m, 2H) and 1.49 (s, 9H) ppm.

Provenance & Evidence