tert-Butyl 2-[3-(bis(tert-butoxycarbonyl)amino)-6-bromo-pyrazin-2-yl]-6-methyl-benzimidazole-1-carboxylate (150 mg, 0.2481 mmol), 2-cyanoacetamide (31.28 mg, 0.3722 mmol), (5-diphenylphosphanyl-9,9-dimethyl-xanthen-4-yl)-diphenyl-phosphane (8.616 mg, 0.01489 mmol) and 1,5-diphenylpenta-1,4-dien-3-one; palladium (4.544 mg, 0.004962 mmol) heated with dicesium carbonate (161.7 mg, 0.4962 mmol) in dioxane for 4 hours at 60° C. The reaction mixture was diluted with EtOAc and washed with water. The organic layer was dried over MgSO4 and concentrated in vacuo. The residue was purified by column chromatography eluting with 20% EtOAc/petroleum ether to give the sub-title product as pale yellow solid which was used directly in the next step.
