Sodium Carbonate → 8-Methyl-2-(p-tolylethynyl)benzo[f][1,7]naphthyridin-5-amine

Participants

Reaction Steps

A solution of 3-chloro-5-(p-tolylethynyl)picolinonitrile (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) (1.2 eq.), tetrakis(triphenylphosphine)palladium (10 mol %), and 2N sodium carbonate aqueous solution (4.0 eq.) in toluene/ethanol (2:1, 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, and the aqueous layer was extracted with 2% MeOH in DCM twice. 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 8-methyl-2-(p-tolylethynyl)benzo[f][1,7]naphthyridin-5-amine.

Provenance & Evidence