Реакция #46392

Уравнение реакции

sulphuric acid

N-(1,1-dioxo-2,3-dihydro-1H-1λ6-benzo[b]thiophen-5-yl)-2-[(E)-hydroxyimino]acetamide

→

desired compound

Выход 52.5%

3,3-dioxo-1,2,3,6-tetrahydro-3λ6-thieno[3,2-e]indole-7,8-dione

Выход 52.5%

Растворители

ethyl acetate

Условия реакции

Обработка

1. 1
   workup.ADDITIONAfter the addition
2. 2
   Температураthe reaction mixture was heated to 90° C.
3. 3
   Температураto cool to RT
4. 4
   workup.STIRRINGbriefly stirred
5. 5
   ДругоеAfter separation of the phases
6. 6
   Другоеthe solid which formed
7. 7
   Фильтрацияwas filtered off with suction
8. 8
   Промывкаwashed with diethyl ether
9. 9
   Другоеdried in a drying oven at 50° C. overnight

Методика

6.74 ml (126.38 mmol) of conc. sulphuric acid were introduced into a three-neck round-bottom flask with thermometer and high-efficiency condenser and heated to 70° C. 3.06 g (12.04 mmol) of N-(1,1-dioxo-2,3-dihydro-1H-1λ6-benzo[b]thiophen-5-yl)-2-[(E)-hydroxyimino]acetamide were then added in portions over the course of half an hour, during which the mixture became dark reddish brown in colour. After the addition was complete, the reaction mixture was heated to 90° C. and stirred at this temperature for one hour. For working up, the reaction mixture was allowed to cool to RT and was then added to a mixture of ice-water (110 ml) and ethyl acetate (25 ml) and briefly stirred. After separation of the phases, the solid which formed was filtered off with suction, washed with diethyl ether and dried in a drying oven at 50° C. overnight. 1.50 g of the desired compound were obtained.

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