反应详情

温度

60 °C

Bromine (26.0 g, 163 mmol) is added to a stirred solution of 4-(4-methoxyphenyl)pyridine (13.6 g. 73.5 mmol) in acetic acid (500 mL) and heated at 60° C. for 72 h. The mixture is then evaporated to dryness under reduced pressure and the residue is treated with aqueous ammonia (400 mL of 6M) and extracted with ethyl acetate (3×200 mL). The combined extracts are dried (Na2SO4), filtered and the solvent is evaporated off under reduced pressure to yield the crude product which is purified by chromatography (silica gel, 95% t-butylmethyl ether/4.5% methanol/0.5% aqueous NH3(25%)) and recrystallised from ether-cyclohexane to give 4-(3-bromo-4-methoxyphenyl)pyridine as a pale-yellow crystalline solid, m.p. 82-84° C.

1. customThe mixture is then evaporated to dryness under reduced pressure
2. additionthe residue is treated with aqueous ammonia (400 mL of 6M)
3. extractionextracted with ethyl acetate (3×200 mL)
4. dry with materialThe combined extracts are dried (Na2SO4)
5. filtrationfiltered
6. customthe solvent is evaporated off under reduced pressure
7. customto yield the crude product which
8. customis purified by chromatography (silica gel, 95% t-butylmethyl ether/4.5% methanol/0.5% aqueous NH3(25%))
9. customrecrystallised from ether-cyclohexane