Potassium Carbonate → 3-Butoxybenzo[f][1,7]naphthyridin-5-amine

Participants

Reaction Conditions

Reaction Steps

A solution of 2-(tert-butoxycarbonylamino)phenylboronic acid (1.0 eq.) and 3-bromo-6-butoxypicolinonitrile (from step 1) (1.0 eq.) in toluene (0.44 M) was mixed with tetrakis(triphenyl-phosphine)palladium (5 mol %) and 2N aqueous potassium carbonate solution (2.0 eq.). The reaction was heated to 100° C. and stirred overnight. After cooling to ambient temperature, the reaction content was diluted with 2% methanol in dichloromethane and water. The two phases were separated, and the aqueous layer was extracted twice with 2% methanol in dichloromethane. The combined organic layers were washed with brine, dried over anhydrous MgSO4, and concentrated en vacuo. The crude product was purified by flash chromatography on a COMBIFLASH® system (ISCO) using 0-5% ethyl acetate in methanol to give 3-butoxybenzo[f][1,7]naphthyridin-5-amine as a white solid. 1H NMR (acetone d-6): δ 8.91 (d, 1H), 8.34 (d, 1H), 7.61 (d, 1H), 7.48-7.52 (dd, 1H), 7.27-7.33 (m, 2H), 6.51 (br, 2H), 6.55 (t, 2H), 1.81-1.88 (m, 2H), 1.50-1.59 (m, 2H), 1.00 (t, 3H). LRMS [M+H]=268.1

Provenance & Evidence