تفاعل #159477

معادلة التفاعل

hydrobromic acid

4′-Chloro-3-methylbiphen-4-ylamine

acetonitrile

butyl nitrite

→

4-bromo-4′-chloro-3-methylbiphenyl

ظروف التفاعل

المعالجة

1. 1
   درجة الحرارةThe reaction mixture is cooled to between −5° C. and 0° C.
2. 2
   درجة الحرارةthe reaction mixture is maintained at between −5 and 0° C. for 30-40 minutes
3. 3
   workup.STIRRINGstirred at 50° C. for 10-15 minutes
4. 4
   درجة الحرارةThe reaction mixture is cooled to room temperature
5. 5
   workup.ADDITIONpoured into ice-cold water
6. 6
   استخلاصextracted with ethyl acetate (3×300 ml)
7. 7
   غسيلThe organic extracts are washed with water
8. 8
   تجفيفdried over anhydrous sodium sulfate
9. 9
   تركيزconcentrated under reduced pressure
10. 10
    أخرىThe residue is purified by column chromatography on silica gel

الإجراء التجريبي

4′-Chloro-3-methylbiphen-4-ylamine (16.5 g, 0.077 mol) is added to acetonitrile (140 ml) and stirred at room temperature until dissolution is complete. The reaction mixture is cooled to between −5° C. and 0° C., tent-butyl nitrite (90%, 12.4 ml, 0.093 mol) is added dropwise and the reaction mixture is maintained at between −5 and 0° C. for 30-40 minutes. The mixture is added slowly to the preheated (50° C.) suspension of copper (I) bromide (5.8 g, 0.04 mol) in hydrobromic acid (5.8 ml) and stirred at 50° C. for 10-15 minutes. The reaction mixture is cooled to room temperature, then poured into ice-cold water and extracted with ethyl acetate (3×300 ml). The organic extracts are washed with water, dried over anhydrous sodium sulfate and concentrated under reduced pressure. The residue is purified by column chromatography on silica gel to yield 4-bromo-4′-chloro-3-methylbiphenyl (11.5 g).

المصدر