تفاعل #2336550

معادلة التفاعل

Ethylene dibromide

N-pivaloyl-4-chloro-3-methoxyaniline

n-butyl lithium

→

N-pivaloyl-2-bromo-4-chloro-3-methoxyaniline

المردود 5.7%

المذيبات

tetrahydrofuran

ظروف التفاعل

المعالجة

1. 1
   workup.STIRRINGthe solution stirred for 18 hours
2. 2
   أخرىbefore being quenched with with ammonium chloride (saturated solution, 20 mL)
3. 3
   استخلاصextracted with ethyl ether (2×50 mL)
4. 4
   غسيلThe combined extracts were washed with brine
5. 5
   تجفيفdried (sodium sulfate)
6. 6
   تركيزconcentrated
7. 7
   أخرىThe residure was purified by chromatography (10% ethyl acetate/hexanes)

الإجراء التجريبي

To solution of N-pivaloyl-4-chloro-3-methoxyaniline (5.0 g, 21 mmol) in tetrahydrofuran (60 mL) at −60° C. was added n-butyl lithium (2.5M, 44 mmol). The solution was allowed to warm to 0° C. and stir for 3 hours. Ethylene dibromide (9.9 g, 53 mmol) was added and the solution stirred for 18 hours before being quenched with with ammonium chloride (saturated solution, 20 mL) and extracted with ethyl ether (2×50 mL). The combined extracts were washed with brine, dried (sodium sulfate) and concentrated. The residure was purified by chromatography (10% ethyl acetate/hexanes) to give N-pivaloyl-2-bromo-4-chloro-3-methoxyaniline (3.7 g, 1.2 mmol): LC/MS (m/z=320).

المصدر