1,8-Diazabicyclo(5.4.0)undec-7-ene → Ethyl 3-(3-nitropyridin-4-yl)-2-oxopropanoate

Participants

Reaction Steps

3.1 g (22.44 mmol) of 4-methyl-3-nitropyridine and 16.39 g (112.22 mmol) of ethyl oxalate are placed in a 100 ml three-necked flask equipped with a magnetic stirrer and maintained under a flush of nitrogen. 3.69 ml (24.69 mmol) of 1,8-diaza-bicyclo[5.4.0]undec-7-ene are then added to the reaction medium stirred at room temperature. The reaction mixture is then stirred at room temperature for 1 hour and then diluted with a mixture of ethyl acetate (150 ml), water (100 ml) and acetic acid (4 ml). The mixture is extracted twice with ethyl acetate. The combined organic phases are washed with 100 ml of water, with 100 ml of saturated aqueous sodium chloride solution, dried over sodium sulfate and then concentrated under reduced pressure. The crude reaction product is then triturated from pentane, filtered and then heated in petroleum ether, filtered and dried under reduced pressure. 3.9 g (16.37 mmol) of product are thus isolated, and are used without further purification in the following step.

Provenance & Evidence