Cesium carbonate → HCID 90135630, compound

Participants

Reaction Steps

Pd(PPh3)4 (0.248 g, 0.215 mmol) was added to a solution of 3E (1.6 g, 4.3 mmol) in 20 mL of 1,4 dioxane-H2O (3:1) mixture under argon atmosphere, followed by cesium carbonate (4.2 g, 12.89 mmol) and 2-bromo-5-nitropyridine (0.872 g, 4.3 mmol). The mixture was degassed for 5 min. The reaction mixture was refluxed for 3 h, and solvent was removed under reduced pressure. The residue was partitioned between ethyl acetate and water. The separated organic layer was dried over sodium sulfate and filtered, and the filtrate was concentrated under reduced pressure. The product was purified by triturating in ethanol to afford the title compound (1.6 g, 69%) as a solid. 1H NMR (400 MHz, CDCl3): δ 9.52 (d, J=2.6 Hz, 1H), 8.57 (dd, J1=2.6 Hz, J2=8.7 Hz, 1H), 8.20 (d, J=8.2 Hz, 1H), 8.02 (s, 1H), 7.97 (dd, J1=3.2 Hz, J2=8.0 Hz, 2H), 4.10 (q, J=7.2 Hz, 2H), 3.19 (m, 1H), 3.06 (dt, J1=17.2 Hz, J2=4.4 Hz, 1H), 2.98 (d, J=15.6 Hz, 1H), 2.56-2.43 (m, 2H), 2.00 (dt, J1=13.5 Hz, J2=4.6 Hz, 1H), 1.31 (s, 3H), 1.22 (t, J=7.2 Hz, 3H). ESI-MS m/z: 369 (M+H)+.

Provenance & Evidence