반응 #4064

반응 방정식

N-methylformanilide

1,4-difluorobenzene

n-butyllithium

sulfuric acid

→

product

수율 77.6%

2,5-Difluorobenzaldehyde

수율 77.6%

용매

tetrahydrofuran

tetrahydrofuran

반응 조건

후처리

1. 1
   기타remained below -55° C
2. 2
   workup.STIRRINGThe mixture was stirred for 1 hr at -50° C.
3. 3
   온도to warm to -30° C. over 15 mins
4. 4
   추출extracted three times with hexane
5. 5
   세척The extracts were washed once with 1N sulfuric acid, once with saturated sodium chloride solution
6. 6
   농축concentrated to an oil
7. 7
   workup.DISTILLATIONDistillation at 64°-65° C. (20 mm)

실험 절차

To a stirred solution of 194.5 g (1.70 mol) of 1,4-difluorobenzene in 2 of dry tetrahydrofuran at -60° C. was added dropwise over 45 mins 1.70 mol (2.2 M in hexane) of n-butyllithium at a rate such that the temperature remained below -55° C. The reaction mixture was stirred for 45 mins at below -50° C. and 1.5 hr at -50° to -45° C. The solution was then cooled to -60° C. and a solution to 230 g of N-methylformanilide in 300 ml of tetrahydrofuran was added dropwise over 30 mins. The mixture was stirred for 1 hr at -50° C. and allowed to warm to -30° C. over 15 mins. The mixture was then poured into ice water, neutralized (pH 6-7) with 10% sulfuric acid and extracted three times with hexane. The extracts were washed once with 1N sulfuric acid, once with saturated sodium chloride solution and concentrated to an oil. Distillation at 64°-65° C. (20 mm) provided 187.5 g (77.5%) of product.

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