Ethyl isocyanate → 1-[3-(3-cyano-1-ethyl-6-methoxy-1H-indol-2-ylethynyl)-phenyl]-3-ethyl urea

Participants

Reaction Conditions

Reaction Steps

2-(3-Aminophenylethynyl)-1-ethyl-6-methoxy-1H-indole-3-carbonitrile (100 mg, 0.32 mmol), prepared as described in Example 1H, is dissolved in pyridine (670 μL). Ethyl isocyanate (62 μL, 0.75 mmol) is added. The reaction mixture is then heated at 100° C. for 2 h. The mixture is then diluted in EtOAc, and is washed with aqueous HCl, followed by brine. The organic layer is dried and concentrated. Purification by silica chromatography (4/1, CH2Cl2/EtOAc), followed by trituration with hexanes/acetone (1/1), yields 1-[3-(3-cyano-1-ethyl-6-methoxy-1H-indol-2-ylethynyl)-phenyl]-3-ethyl urea (44 mg, 36%) as a white solid.

Provenance & Evidence