2-Isopropoxy-6-(trimethylstannyl)pyrazine → 3-(3-(6-isopropoxypyrazin-2-yl)-1-tosyl-1H-indol-5-yl)-1,2,4-oxadiazol-5-amine

Participants

Reaction Conditions

Reaction Steps

Argon gas was bubbled through a solution of 3-(3-iodo-1-tosyl-1H-indol-5-yl)-1,2,4-oxadiazol-5-amine (250 mg, 0.52 mmol) and 2-isopropoxy-6-(trimethylstannyl)pyrazine (188 mg, 0.62 mmol) in dry DMF (2.5 mL) for 15 min. To the mixture was added CuI (99 mg, 0.52 mmol) and Pd(PPh3)4 (60 mg, 0.052 mmol) and argon gas was further bubbled for additional 15 min. The reaction was heated at 90° C. for 1 h then cooled to RT. The reaction was quenched with ice cold water. The resulting suspension was filtered and washed with water. The solid was purified with basic alumina column chromatography (eluent: 20% EtOAc in petroleum ether) to give 3-(3-(6-isopropoxypyrazin-2-yl)-1-tosyl-1H-indol-5-yl)-1,2,4-oxadiazol-5-amine (150 mg, 59%). MS (ESI, pos. ion) m/z: 491.1 (M+1).

Provenance & Evidence