Cesium carbonate → ethyl 1-{[6-(1-methyl-1H-pyrazol-4-yl)pyridin-3-yl)methyl}-4-oxo-1,4-dihydrocinnoline-3-carboxylate

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Reaction Steps

Ethyl 1-[(6-bromopyridin-3-yl)methyl]-4-oxo-1,4-dihydrocinnoline-3-carboxylate [(Example 83, Step 1), 748 mg, 1.93 mmol] and 1-methyl-4-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)-1H-pyrazole (682 mg, 3.28 mmol, 1.7 equiv) were suspended in tetrahydrofuran (15 mL) and treated with an aqueous solution (1.5 mL) of cesium carbonate (1.26 g, 3.85 mmol, 2 equiv). The mixture was sparged under nitrogen, treated with bis(tri-tert-butylphosphine)palladium(0) (197 mg, 0.385 mmol, 0.2 equiv) and placed in an oil bath preheated to 80° C. for 1 hour. The mixture was cooled to ambient temperature, poured into sodium bicarbonate (75 mL, aqueous saturated) and extracted with ethyl acetate (2×100 mL). The combined organic extracts were dried with sodium sulfate, filtered and concentrated in vacuo. The residue was purified by silica gel gradient chromatography (100:0 to 0:100; hexanes:ethyl acetate), providing the titled compound.

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