Sulfuric acid magnesium salt (1:1) → 3-Bromothieno[3,2-b]pyridine

Participants

Reaction Steps

3.45 g of Thieno[3,2-b]pyridine (25.6 mmol), 2.15 g of sodium bicarbonate (25.6 mmol), 6.69 g of K2HPO4 (38.4 mmol) and 4.01 g of MgSO4 (33.3 mmol) are placed in the flask with 60 ml of CHCl3. The mixture is stirred under reflux and 1.57 ml of Br2 (30.7 mmol) is added slowly. The reaction mixture is stirred under reflux overnight. Additional 0.7 ml of bromine is added and stirred under reflux for 4 h and cooled to room temperature. Water is added and extracted with CHCl3. The separated CHCl3 is washed by sat. Na2S2O3 and sat. NaCl and dried over Na2SO4 and evaporated. The title compound is recrystallized from Hexane/CH2Cl2. 3.94 g, Yield 72%. mass spectrum (m/e): 215 (M+1); 1H-NMR (CDCl3): 8.86 (d, 1H, J=5.2 Hz), 8.24 (d, 1H, J=8.2 Hz), 7.82 (s, 1H), 7.38 (dd, 1H, J=8.2 Hz, 5.2 Hz) ppm.

Provenance & Evidence