2-Bromo-5-methylpyrazine → tert-Butyl 4-(2-(1-(5-methylpyrazin-2-yl)piperidin-4-yloxy)benzo[d]thiazol-6-yl)-5,6-dihydropyridine-1 (2H)-carboxylate

Participants

Reaction Conditions

Reaction Steps

To a degassed solution of tert-butyl 4-(2-(piperidin-4-yloxy)benzo[d]thiazol-6-yl)-5,6-dihydropyridine-1(2H)-carboxylate (119.4 mg, 0.287 mmol), 2-bromo-5-methylpyrazine (99 mg, 0.575 mmol), t-BuONa (83 mg, 0.862 mmol), and BINAP (3.58 mg, 5.75 μmol) in toluene (2.5 mL) was added Pd2(dba)3 (15.79 mg, 0.017 mmol). The reaction mixture was stirred in a seal vial at 80° C. overnight, then at 90° C. for additional 2.5 h. The mixture was cooled to rt, diluted with water (10 mL), and extracted with EtOAc (3×5 mL). The combined organic layers were washed with brine (8 mL), dried (Na2SO4), and concentrated. The residue was purified by column chromatography (silica gel, hexanes-EtOAc gradient 0 to 70% EtOAc) to afford Compound 50B (86.6 mg, 0.171 mmol, 59% yield) as a light orange solid. 1H NMR (500 MHz, CDCl3) δ 8.11 (s, 1H), 7.97 (s, 1H), 7.62 (dd, J=9.9, 5.0 Hz, 2H), 7.40 (dd, J=8.5, 1.6 Hz, 1H), 6.04 (s, 1H), 5.44 (dt, J=7.6, 3.8 Hz, 1H), 4.09 (s, 2H), 3.97-3.84 (m, 2H), 3.65 (d, J=5.2 Hz, 2H), 3.57-3.43 (m, 2H), 2.55 (s, 2H), 2.41 (s, 3H), 2.28-2.13 (m, 2H), 2.08-1.94 (m, 2H), 1.50 (s, 9H). LCMS (m/z)=508 (M+H)+.

Provenance & Evidence