تفاعل #67693

معادلة التفاعل

Dimethyl disulfide

sec-butyllithium

2-Methoxy-4-trifluoromethyl-benzoic acid

→

title compound

المردود 11.1%

2-Methoxy-6-methylsulfanyl-4-trifluoromethyl-benzoic acid

المردود 11.1%

المذيبات

tetrahydrofuran

tetrahydrofuran

ظروف التفاعل

المعالجة

1. 1
   workup.ADDITIONAfter complete addition
2. 2
   workup.STIRRINGStirring
3. 3
   workup.WAITwas continued at −70° C. for another hour
4. 4
   درجة الحرارةto warm up
5. 5
   أخرىThe reaction mixture was quenched with 150 mL water
6. 6
   استخلاصextracted with 200 mL ethyl acetate
7. 7
   workup.ADDITIONThe aqueous phase was adjusted to pH1 by addition of 25% HCl
8. 8
   استخلاصextracted twice with dichloromethane
9. 9
   أخرىThe combined organic phases were dried on sodium sulfate
10. 10
    ترشيحfiltered
11. 11
    أخرىevaporated
12. 12
    أخرىThe crude product was crystallized with heptane

الإجراء التجريبي

N,N,N′N′-Tetramethylethylendiamine (21 g, 177 mmol) was added drop-wise at −70° C. to a solution of sec-butyllithium (110 mL, 1.4 M in cyclohexane, 154 mmol) in 180 mL tetrahydrofuran. 2-Methoxy-4-trifluoromethyl-benzoic acid (13 g, 59 mmol) in 60 mL tetrahydrofuran was added drop-wise at −70° C. over 2 hours. After complete addition stirring was continued at −70° C. for another 2 hours. Dimethyl disulfide (20 g, 207 mmol) was added at −70° C. within 10 min. Stirring was continued at −70° C. for another hour and the reaction was allowed to warm up. The reaction mixture was quenched with 150 mL water and extracted with 200 mL ethyl acetate. The aqueous phase was adjusted to pH1 by addition of 25% HCl and extracted twice with dichloromethane. The combined organic phases were dried on sodium sulfate, filtered and evaporated. The crude product was crystallized with heptane and yielded the title compound as a white solid (1.75 g, 11%), MS: m/e=265.1 [(M−H)−].

المصدر