Sodium Carbonate → 6-(1H-indol-4-yl)-1H-indazol-4-amine

Participants

Reaction Conditions

Reaction Steps

6-Bromo-1H-indazol-4-amine (10 g) (available from Sinova Inc.) and 4-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)-1H-indole (16.05 g) (available from Frontier Scientific, Europe Ltd) were dissolved in 1,4-dioxane (60 ml) and water (60 ml). 2M sodium carbonate (70.7 ml) and Pd(dppf)Cl2-DCM adduct (1.93 g) were added and the mixture was heated at 115° C. for 18 h. The reaction mixture was diluted with DCM (200 ml) and the organic and aqueous layers were separated using a hydrophobic frit. The aqueous layer was extracted with further quantities of DCM (2×200 ml), using a hydrophobic frit to separate the layers. The organic layers were combined and silica (80 g) was added. The solvent was removed in vacuo to give a crude material that was purified by chromatography on silica gel (750 g cartridge, Flashmaster II) eluting with 0-100% ethyl acetate in cyclohexane over 60 min. The oil was dried in vacuo on a drying rack overnight. The yellow foam was dissolved in DCM (3×400 ml), removing the solvent in vacuo after each dissolution. ethyl acetate (50 ml) was then added and the solvent was removed in vacuo. The solid obtained was dried in a vacuum oven to afford the title compound (12.8 g) as a yellow foam.

Provenance & Evidence