Under an inert gas atmosphere is dissolved 5-(4-iodo-phenyl)-7-methylsulfanyl-pyrazolo[1,5-c]pyrimidine (compound D1)(0.45 g) and phenylboronic acid (0.35 g) in dimethoxyethane. To this solution are added bis-(triphenylphosphine)-palladium(II) chloride (0.19 mmol) and an aqueous sodium carbonate solution (2M, 6 ml). The reaction mixture is heated to reflux for 4.5 h. After 1 h further phenylboronic acid (0.2 g) is added in order to complete the reaction. The mixture is diluted with ethyl acetate and filtered over silica gel. The product is partitioned between ethyl acetate and an aqueous solution of sodium bicarbonate (5%), the organic phase is dried over sodium sulfate and the crude product is purified by silica gel flash chromatography. A nearly colorless solid (0.3 g) in 50% yield is obtained.
