反应详情

A solution of 20 ml of 1.6N n-butyllithium in hexane is added dropwise within 30 minutes, with stirring and with the exclusion of moisture, to a solution, cooled to -75°, of 5.2 g (33 mmol) of 5-bromopyrimidine and 10.7 g (31.2 mmol) of 4,4'-dibromobenzophenone in 130 ml of THF. The reaction mixture is stirred for a further 0.5 hour at -75° and then for 16 hours at room temperature; then, while cooling with ice, it is hydrolysed by adding 20 ml of water. The organic phase is separated and diluted with ethyl acetate. The solution is washed with 2N HCl and a semi-saturated sodium chloride solution, dried over sodium sulfate, filtered and concentrated by evaporation. The residue is purified by column chromatography (400 g of silica gel, methylene chloride/ethyl acetate 85:15) and recrystallised from ethyl acetate, m.p. 89°-90°, Rf value=0.11 (silica gel, methylene chloride/ethyl acetate 85:15).

1. stirringThe reaction mixture is stirred for a further 0.5 hour at -75°
2. temperaturethen, while cooling with ice, it
3. customThe organic phase is separated
4. additiondiluted with ethyl acetate
5. washThe solution is washed with 2N HCl
6. dry with materiala semi-saturated sodium chloride solution, dried over sodium sulfate
7. filtrationfiltered
8. concentrationconcentrated by evaporation
9. customThe residue is purified by column chromatography (400 g of silica gel, methylene chloride/ethyl acetate 85:15)
10. customrecrystallised from ethyl acetate, m.p. 89°-90°, Rf value=0.11 (silica gel, methylene chloride/ethyl acetate 85:15)