تفاعل #7053

معادلة التفاعل

methyl alcohol

dimethylformamide

water

ethyl acetate

5-bromothiophene-2-sulfonamide

dimethylformamide

→

title compound

5-(Cyano)thiophene-2-sulfonamide

المذيبات

methylene chloride

ظروف التفاعل

المعالجة

1. 1
   workup.WAITplaced under microwave radiation (under nitrogen atmosphere at 160° C.) for 37 min
2. 2
   أخرىThe organic phase is separated
3. 3
   استخلاصthe aqueous layer is extracted with 20 mL ethyl acetate
4. 4
   تجفيفThe combined organic layers are dried over sodium sulfate
5. 5
   تركيزconcentrated in vacuo
6. 6
   أخرىchromatographed on silica (0–5% methyl alcohol in methylene chloride)

الإجراء التجريبي

A mixture of 5-bromothiophene-2-sulfonamide (0.50 g, 2.1 mmol), zinc cyanide (0.25 g, 2.1 mmol), tetrakis(triphenylphosphine)palladium(0) (0.072 g, 0.06 mmol) in dimethylformamide (5 mL, anhydrous) is placed under microwave radiation (under nitrogen atmosphere, 160° C.) for 15 min. Thin layer chromatography (5% methyl alcohol in methylene chloride) demonstrates the reaction is incomplete. Additional tetrakis-(triphenylphosphine)palladium(0) (0.24 g, 0.2 mmol) and dimethylformamide (10 mL) are added to the reaction mixture and placed under microwave radiation (under nitrogen atmosphere at 160° C.) for 37 min. 10 mL of water and 20 mL of ethyl acetate are added to the reaction mixture. The organic phase is separated and the aqueous layer is extracted with 20 mL ethyl acetate. The combined organic layers are dried over sodium sulfate, concentrated in vacuo, and then chromatographed on silica (0–5% methyl alcohol in methylene chloride) to give the title compound, as a white solid (0.22 g, 57% yield).

المصدر