Dichloromethane → 6-Hydroxy-2-(3-methoxy-6-pyridin-4-yl-pyridazin-4-yl)-indole-1-carboxylic acid tert-butyl ester

Participants

Reaction Steps

600 mg 4-Iodo-3-methoxy-6-pyridin-4-yl-pyridazine, 974 mg 1-(tert-butoxycarbonyl)-6-(tert-butyldimethylsiloxy)indole-2-boronic acid, 2.5 g cesium carbonate, and 78 mg [1,1′-bis(diphenylphosphino)ferrocene]dichloropalladium(II) complex with dichloromethane (1:1) are dissolved in a mixture of 18 mL dioxane and 5.4 mL water. Argon is bubbled through the solution for 5 minutes. The mixtures is heated to reflux for 2 hours. After diluting with EtOAc, the organic phase is ished with water and brine, dried with MgSO4 and concentrated in vacuo. The crude product is dissolved in 30 mL THF. After addition of 1.51 g tetrabutylammonium fluoride trihydrate, the red solution is stirred for 2 hours. The reaction mixture is diluted with EtOAc, ished with saturated aqueous ammonium chloride, water, and brine, dried with MgSO4 and concentrated in vacuo. Purification by HPLC afforded 760 mg (95%) 6-hydroxy-2-(3-methoxy-6-pyridin-4-yl-pyridazin-4-yl)-indole-1-carboxylic acid tert-butyl ester.

Provenance & Evidence