تفاعل #1581028

معادلة التفاعل

reactin

tBuLi

4-Bromotoluene

dimethyl-2-bromo-terepthalate

→

desired product

المردود 85.3%

Dimethyl-2-(4-toluyl)-terepthalate

المردود 85.3%

المذيبات

tetrahydrofuran

tetrahydrofuran

ظروف التفاعل

المعالجة

1. 1
   workup.ADDITIONTo this solution at -78° C. under N2 was added over a ten minute period
2. 2
   workup.WAITAfter one half hour at room temperature
3. 3
   أخرىThe tetrahydrofuran was removed under reduced pressure
4. 4
   workup.ADDITIONThe residue was treated with ethyl acetate and 1N HCl
5. 5
   أخرىthe layers separated
6. 6
   غسيلThe organic phase was washed with water, brine
7. 7
   تجفيفdried over magnesium sulfate
8. 8
   أخرىevaporated
9. 9
   أخرىgave the crude product

الإجراء التجريبي

4-Bromotoluene (6 g) was dissolved in tetrahydrofuran (20 ml). To this solution at -78° C. under N2 was added over a ten minute period, 1.7M tBuLi (42 ml). After two hours at room temperature, the reaction mixture was cooled to 0° C. and 1M ZnCl2 (36 ml) was added over a ten minute period. After one half hour at room temperature, bis(triphenylphosphine)nickel(II) chloride (1.32 g) was added followed by dimethyl-2-bromo-terepthalate (6 g) in tetrahydrofuran (20 ml) dropwise over a five minute period. The reactin mixture was stirred at room temperature for two hours. The tetrahydrofuran was removed under reduced pressure. The residue was treated with ethyl acetate and 1N HCl and the layers separated. The organic phase was washed with water, brine, dried over magnesium sulfate and evaporated gave the crude product. Chromatography on silica gel using 5% hexanes/methylene chloride gave the desired product (5.33 g).

المصدر