To a round bottom flask was added 2-((1H-indol-5-yl)ethynyl)-8-methylbenzo[f][1,7]naphthyridin-5-amine (from the previous step) (1 eq.) with a stirring bar. Ethanol and methylene chloride (1:2, 0.2 M) were added, followed by palladium in carbon (activated powder, wet, 10% on carbon, 0.1 eq.). The content were vacuumed followed by hydrogen flush for three times. The reaction mixture was stirred vigorously under hydrogen balloon at room temperature overnight. Afterwards the reaction mixture was filtered through a celite pad, and the celite pad was washed subsequently with methylene chloride and EtOAc until the filtrate had no UV absorption. Combined organic washes were concentrated. Flash chromatography (silica gel, 0-50% EtOAc in CH2Cl2) afforded the product 2-(2-(2,3-Dihydrobenzofuran-5-yl)ethyl)-8-methylbenzo[f][1,7]naphthyridin-5-amine as a yellow solid. 1H NMR (CDCl3): δ 8.54 (d, 1H), 8.34 (d, 1H), 8.28 (s, 1H), 7.99 (d, 1H), 7.64-7.56 (m, 1H), 7.50-7.35 (m, 1H), 7.24 (d, 1H), 7.12 (t, 1H), 7.08 (dd, 1H), 6.92 (dd, 1H), 6.41 (s, 1H), 6.01 (bs, 2H), 3.16-3.12 (m, 2H), 3.10-3.05 (m, 2H), 2.43 (s, 3H). LRMS [M+H]=353.2
