反应详情

26 g of 3-methyl-2-thiophenecarboxaldehyde was dissolved in 100 ml of chloroform and the solution was stirred by cooling with ice 11 ml of bromine was added dropwise thereto. The temperature was elevated to room temperature and the mixture was stirred overnight. About 1 l of ethyl acetate was added thereto and the mixture was washed with water, then with a saturated aqueous sodium hydrogencarbonate solution and finally with a saturated aqueous common salt solution. After drying over anhydrous magnesium sulfate, the solvent was distilled off under reduced pressure to give 46.8 g of 5-bromo-3-methyl-2-thiophenecarboxaldehyde in the form of a dark brown solid, which was subjected to the subsequent reaction without purification.

1. additionwas added dropwise
2. customwas elevated to room temperature
3. stirringthe mixture was stirred overnight
4. washthe mixture was washed with water
5. dry with materialAfter drying over anhydrous magnesium sulfate
6. distillationthe solvent was distilled off under reduced pressure