Reaction Steps
To a solution of 3-bromo-5-[[1-(tert-butoxycarbonyl)-2(S)-pyrrolidinyl]methoxy]pyridine (70 mg, 0.20 mmol) and indoline (25 μL, 0.22 mmol, 1.1 equiv.) in anhydrous toluene (2 mL) were added successively sodium tert-butoxide (29 mg, 0.3 mmol, 1.5 equiv.), tris(dibenzylideneacetone)dipalladium(0) (3.7 mg, 4.0 μmol, 0.02 equiv.), and 4,5-bis(diphenylphosphino)-9,9-dimethylxanthene (Xantphos; 6.9 mg, 12 μmol, 0.06 equiv.). The mixture was degassed and purged with Ar (3 cycles), then warmed to 98-100° C. for 4 h. After cooling to room temperature, the mixture was diluted with EtOAc, and the solution was washed with brine, dried over Na2SO4, and evaporated. The residue was purified by CC (SiO2, CH2Cl2/EtOAc 4:1, then 1:1). The product (71 mg, 90%) was obtained as a bright yellow oil. 1H NMR (CDCl3, 400 MHz) δ 8.19 (s, 1H), 7.91 (s, 1H), 7.20-7.00 (m, 4H), 6.79 (t, 1H, J=6.8 Hz), 4.11 (m, 2H), 3.90-3.86 (m, 3H), 3.41 (m, 2H), 3.13 (t, 2H, J=8.4 Hz), 2.02 (m, 3H), 1.86 (m, 1H), 1.46 (s, 9H); 13C NMR (CDCl3, 100 MHz) δ 155.6, 146.0, 141.4, 132.1, 131.5, 130.1, 129.1, 127.3, 125.3, 120.0, 109.4, 108.7, 68.5, 56.1, 51.9, 47.1, 46.8, 28.9, 28.6, 28.2, 24.0.
