Potassium Carbonate → 2-(Benzyloxy)benzo[f][1,7]naphthyridin-5-amine

Participants

Reaction Conditions

Reaction Steps

A solution of 2-(tert-butoxycarbonylamino)phenylboronic acid (1.0 eq.) and 5-(benzyloxy)-3-bromopicolinonitrile (from step 3) (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 50-100% ethyl acetate in hexane to give 2-(benzyloxy)benzo[f][1,7]naphthyridin-5-amine. 1H NMR (acetone d-6): δ 8.36 (s, 1H), 7.86 (s, 1H), 7.59-7.56 (d, 2H), 7.46-7.42 (dd, 2H), 7.40-7.37 (d, 1H), 7.20-7.15 (dd, 1H), 7.12-7.09 (d, 1H), 6.88-6.86 (d, 1H), 6.77-6.73 (dd, 1H), 5.51 (s, 2H), 4.74 (br, 2H). LRMS [M+H]=302.3.

Provenance & Evidence