تفاعل #65867

معادلة التفاعل

ethoxymethylenecyanoacetic acid methyl ester

toluene

toluene

2,2-difluoro-1,3-benzodioxole

n-butyllithium

TMEDA

→

title compound

(E)-2-cyano-3-(2,2-difluoro-1,3-benzodioxol-4-yl)-2-propenoic acid ethyl ester

المذيبات

water

ظروف التفاعل

المعالجة

1. 1
   أخرىat from -15° to -10° C.
2. 2
   أخرىthe phases are separated
3. 3
   تركيزthe organic phase is concentrated by evaporation in a vacuum rotary evaporator

الإجراء التجريبي

53.3 g (337 mmol) of 2,2-difluoro-1,3-benzodioxole in 46 ml of toluene are metalated according to Example 2d), at from -15° to -10° C., with 137.8 g (409 mmol) of n-butyllithium solution (19.0% in toluene) in the presence of 39.3 g (339 mmol) of TMEDA. 69.1 g (409 mmol) of ethoxymethylenecyanoacetic acid methyl ester in 150 ml of toluene are metered in at from -15° to -10° C. over a period of 21/2 hours. The reaction mixture is added at +10° C. to 450 ml of water, the phases are separated and the organic phase is concentrated by evaporation in a vacuum rotary evaporator to yield the title compound.

المصدر