Cesium carbonate → 4-(2-Fluoro-4-nitrophenoxy)-6,7-dimethoxyquinoline

Participants

Reaction Conditions

Reaction Steps

A mixture of 6,7-dimethoxyquinolin-4-ol (1.4 g, 6.8 mmol, 1.0 eq.), 3,4-difluoro-nitrobenzene (1.44 g, 8.84 mmol, 1.3 eq.) and cesium carbonate (3.6 g, 10.9 mmol, 1.6 eq.) in dry DMF (10 mL) was heated for 1 h at 50° C. in a microwave oven. After cooling to RT the mixture was diluted with water and extracted with EtOAc. The combined organic phase was dried over Na2SO4 and evaporated in vacuo. The crude product was purified by flash chromatography on silica gel (DCM/MeOH=100:0 to 5:1) to yield the desired product A1 (909 mg, 2.64 mmol, 38.8%) as a yellow solid. 1H NMR (400 MHz, CDCl3, 300K) δ 4.04 (s, 3H), 4.06 (s, 3H), 6.55 (d, J=5.2 Hz, 1H), 7.34 (dd, J=7.8 Hz, J=8.8 Hz, 1H), 7.44 (s, 1H), 7.46 (s, 1H), 8.13 (m, 1H), 8.19 (dd, J=9.8 Hz, J=2.5 Hz, 1H), 8.58 (d, J=5.2 Hz, 1H). MS (ES) C17H13FN2O5 requires: 344, found: 345 (M+H)+. Furthermore an isomer (941 mg, 2.74 mmol, 40.2%) was isolated as a yellow solid. MS (ES) C17H13FN2O6 requires: 344. Found: 345 (M+H)+.

Provenance & Evidence