تفاعل #657251

معادلة التفاعل

ammonium chloride

n-butyllithium

19

5,7-Dibromo-2,3-dihydrobenzofuran

N,N-dimethylformamide

→

crystals

المردود 27.1%

5-Bromo-2,3-dihydrobenzofuran-7-carbaldehyde

المردود 27.1%

المذيبات

THF

ظروف التفاعل

المعالجة

1. 1
   أخرىwas degassed at −78° C.
2. 2
   أخرىThe solvent was removed
3. 3
   غسيلwashed with water (3×50 mL)
4. 4
   تجفيفthen dried with anhydrous sodium sulfate
5. 5
   أخرىSolvent removal

الإجراء التجريبي

A sample of 19 (6.0 g, 26.5 mmol) in freshly distilled dry THF was degassed at −78° C. and n-butyllithium (25 mL of 1.05 M, 26 mmol) was added dropwise by syringe. Then N,N-dimethylformamide (2.9 mL, 26 mmol) was added dropwise via syringe. The reaction mixture was allowed to come to room temperature overnight. Saturated ammonium chloride (10 mL) was added to and the mixture was stirred for 30 minutes. The solvent was removed and the residue was taken up in dichloromethane (50 mL), and washed with water (3×50 mL) then dried with anhydrous sodium sulfate. Solvent removal yielded yellow crystals (1.6 g) which were washed with ether and recrystallized from a minimum of hot methanol to give white crystals of 20 (1.32 g, 22%) mp=99-100° C.

المصدر