Hydrochloric Acid → (R)-6-(5-(6-isopropoxypyrazin-2-yl)-1H-indol-3-yl)-N-(piperidin-3-yl)pyrazin-2-amine

Participants

Reaction Steps

To a solution of (R)-tert-butyl 3-(6-(5-(6-isopropoxy-pyrazin-2-yl)-1-tosyl-1H-indol-3-yl)pyrazin-2-ylamino)piperidine-1-carboxylate (0.250 g, 0.365 mmol) in 1-4-dioxane (3.6 mL), 1N NaOH (3.6 mL) was added and heated at 100° C. for 2 h. The reaction mixture was quenched with ice cold water and precipitate was formed. The precipitate was collected by filtration, washed with ice cold water and dried to give pure (R)-tert-butyl 3-(6-(5-(6-isopropoxypyrazin-2-yl)-1H-indol-3-yl)pyrazin-2-ylamino)piperidine-1-carboxylate (180 mg, 93%). MS (ESI, pos. ion) m/z: 530.0 (M+1). To a solution of (R)-tert-butyl 3-(6-(5-(6-isopropoxypyrazin-2-yl)-1H-indol-3-yl)pyrazin-2-ylamino)piperidine-1-carboxylate (180 mg, 1.25 mmol) in EtOAc (5.0 mL) was treated with HCl in EtOAc (5.0 mL) and stirred at RT for 3 h. The reaction mixture was quenched with water, neutralized with NaHCO3, extracted with EtOAc. The organic layer was separated, dried over Na2SO4 and evaporated to dryness. The crude solid was re-crystallized in acetone to obtain (R)-6-(5-(6-isopropoxypyrazin-2-yl)-1H-indol-3-yl)-N-(piperidin-3-yl)pyrazin-2-amine. MS (ESI, pos. ion) m/z: 430.0 (M+1).

Provenance & Evidence