To a stirred solution of 3-iodo-1-methyl-4-nitro-1H-pyrrolo[2,3-b]pyridine (D17) (6.2 g, 20.46 mmol) in ACN (108 mL) was added 1-methyl-6-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)indoline (7.95 g, 30.7 mmol), bis(triphenylphosphine)palladium(II) chloride (1.436 g, 2.046 mmol) and 2M sodium carbonate aq. solution (108 mL, 217 mmol). The resulting mixture was heated at 65° C. for ca. 1 hour. After being cooled to RT, the reaction mixture was diluted with DCM (150 mL) and water (200 mL). The organic phase was separated and the aqueous phase was further extracted with DCM (80 mL×4). The combined organics were dried and concentrated. The residue was purified by chromatography on silica, eluting with a gradient of 0-100% ethyl acetate in cyclohexane to give an impure fraction which was re-purified by chromatography on silica, eluting with a gradient of 0-20% ethyl acetate in DCM to give the title compound (3.14 g). LCMS (A): m/z (M+H)+ 309, C17H16N4O2 requires 308 (acidic).
