Potassium Carbonate → Ethyl 4-((5-amino-8-methylbenzo[f][1,7]naphthyridin-2-yl)ethynyl)-3-methylbenzoate

Participants

Reaction Steps

A solution of ethyl 4-((5-chloro-6-cyanopyridin-3-yl)ethynyl)-3-methylbenzoate (from the previous step) (1.0 eq.), tert-butyl 5-methyl-2-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)phenylcarbamate (from Example 5/Step 2) (1.1 eq.), tetrakis(triphenylphosphine)palladium (8 mol %), and potassium carbonate (3.0 eq.) in toluene/ethanol (9:1, 0.2 M) was stirred at 100° C. overnight. After cooling to ambient temperature, the reaction mixture was diluted with 2% MeOH in DCM. The two phases were separated. The combined organic layers were washed with brine, dried over anhydrous MgSO4, and concentrated en vaccuo. The crude material was purified by flash chromatography on a COMBIFLASH® system (ISCO) using 0-40% ethyl acetate in toluene to give ethyl 4-((5-amino-8-methylbenzo[f][1,7]naphthyridin-2-yl)ethynyl)-3-methylbenzoate.

Provenance & Evidence