Potassium Carbonate → 8-Bromo-1,2,3,4-tetrahydronapthyridine

Participants

Reaction Steps

To a solution of 0.6730 g (5.02 mmol) 32 in 20 mL glacial acetic acid was added 1.0701 g (6.01 mmol) N-bromosuccinimide. After 16 h at 65° C., the reaction mixture was cooled to room temperature and poured onto 50 mL ice water. This was brought to pH 11 with K2CO3 and extracted with 4×100 mL CHCl3. The combined CHCl3 extracts were washed with 100 mL brine, dried over Na2SO4, filtered and concentrated in vacuo. Purification by flash chromatography (50×115 mm silica gel, linear gradient 2-5% (10% NH4H:MeOH):CH2Cl2) yielded 33. 1H NMR (CDCl3, 400 MHz) δ 8.175 (s, 1H, ArH); 7.877 (s, 1H, ArH); 3.458-3.423 (m, 2H, CH2); 2.725 (t, 2H, J=6.26 Hz, CH2); 1.970-1.911 (m, 2H, CH2); MS (Electrospray): m/z 212.9, 214.8 (M+H, 79Br, 81Br).

Provenance & Evidence