反応 #1269817

反応方程式

benzo[b]thiophene-2-sulfonyl chloride

nitric acid

→

product

Mono nitro-benzo[b]thiophene-2-sulfonyl chloride

溶媒

dichloromethane

反応条件

後処理

1. 1
   温度the resulting mixture was refluxed overnight
2. 2
   その他The organic layer was separated
3. 3
   抽出the aqueous layer was extracted by 220 mL 2 dichloromethane
4. 4
   乾燥dried over MgSO4
5. 5
   その他Solvent was then removed by rotary evaporator
6. 6
   その他The crude product was purified by flash column chromatography with an eluent of hexane

実験手順

To a solution of benzo[b]thiophene-2-sulfonyl chloride (1.165 g, 5 mmol) in 25 mL of dichloromethane was added 3.6 mL of concentrated nitric acid (≧22.05 mol/L) dropwise, the resulting mixture was refluxed overnight and cooled to room temperature before it was poured into 20 gram of crushed ice. The organic layer was separated and the aqueous layer was extracted by 220 mL 2 dichloromethane. The organic layers were combined and dried over MgSO4. Solvent was then removed by rotary evaporator. The crude product was purified by flash column chromatography with an eluent of hexane, followed by a gradient eluent of hexane/ethyl acetate (6/1-3/1) to afford 0.58 g of product (mixture of 65% of 4-nitro-benzo[b]thiophene-2-sulfonyl chloride and 35% of 7-nitro-benzo[b]thiophene-2-sulfonyl chloride).

出典