反应详情

A solution of 7.05 g (30 mmol) of 6-bromo-2,2'-bipyridine in 50 ml of diethyl ether is added to a solution of 19.4 ml (31 mmol) of 1.6M butyllithium-in-hexane solution in 100 ml of diethyl ether at -80° C. under a nitrogen atmosphere. After the addition is complete, stirring is carried out for a further 30 minutes at this temperature, after which a solution of 4.39 g (60 mmol) of dimethylformamide in 30 ml of diethyl ether is added at from -80° to -90° C. After further stirring at this temperature for 1.5 hours, hydrolysis is carried out with 150 ml of quarter-concentrated hydrochloric acid at from -60° to -50° C. The reaction mixture is then neutralized at room temperature by adding solid sodium bicarbonate, the phases are separated and the aqueous phase is extracted once again with 50 ml of diethyl ether. The organic phases are combined and are dried over sodium sulfate and finally the solvent is distilled off under reduced pressure. The title compound is obtained as a reddish brown oil which crystallizes on standing.

1. additionAfter the addition
2. stirringAfter further stirring at this temperature for 1.5 hours
3. customhydrolysis
4. customis then neutralized at room temperature
5. customthe phases are separated
6. extractionthe aqueous phase is extracted once again with 50 ml of diethyl ether
7. dry with materialare dried over sodium sulfate
8. distillationfinally the solvent is distilled off under reduced pressure