73882-41-4

3141-26-2

73882-41-4

1) 3,4-dibromothiophene (24.2 g, 100 mmol) was dissolved in anhydrous ether and cooled under nitrogen protection to -78°C. n-Butyllithium (66 mL, 105 mmol, 1.6 M solution) was slowly added dropwise and the reaction was maintained at a temperature of -78°C for 1 hour. Subsequently, iodine (26.67 g, 105 mmol) was added and stirring was continued at -78°C for 1 h. The reaction was then slowly warmed to room temperature (25°C). After completion of the reaction, the reaction was quenched with sodium bisulfite solution and the organic layer was extracted with ether. The organic layer was dried over magnesium sulfate and the solvent was removed by distillation under reduced pressure to give 3-bromo-4-iodothiophene (22.55 g, 78% yield) as a colored liquid.