Potassium Iodide → 4-[2-((R)-1-Phenyl-ethylamino)-quinoxalin-6-yl]-pyrazole-1-carboxylic acid tert-butyl ester

Participants

Reaction Conditions

Reaction Steps

A mixture of (6-Bromo-quinoxalin-2-yl)-((R)-1-phenyl-ethyl)-amine (0.42 g, 1 eq, 1.28 mmol), 1-boc-4-pyrazole boronic acid pinacol ester (0.45 g, 1.2 eq, 1.53 mmol), caesium carbonate (1.66 g, 4.0 eq, 5.1 mmol) and potassium iodide (0.021 g, 0.1 eq, 0.13 mmol) in 1,4-dioxane (20 mL) was degassed at RT under vacuum and then placed under an atmosphere of nitrogen. The process was repeated twice and Fu's catalyst (Bis(tri-tert-butylphosphine)palladium(0)) (0.033 g, 0.05 eq, 0.06 mmol) was added at room temperature. The reaction mixture was heated at 108° C. in a microwave reactor for 180 minutes. After completion of the reaction (confirmed by TLC), the reaction mixture was diluted with ethyl acetate (200 mL) and then washed with water (50 mL×3) and brine (50 mL). The organic layer was dried and concentrated to give the crude product.

Provenance & Evidence