反应 #923

反应方程式

sulfur dioxide

n-butyllithium

N-methyl-pyrrole

t-butylamine

→

title compound

收率 28.5%

N-(1,1-Dimethylethyl)-1-methyl-1H-pyrrole-2-sulfonamide

收率 28.5%

溶剂

THF

反应条件

后处理

1. 1
   其他the temperature below -60° C
2. 2
   workup.ADDITIONwas added rapidly
3. 3
   其他at -20° C.
4. 4
   workup.STIRRINGAfter stirring for 1 h at ambient temperature
5. 5
   其他the THF was removed under reduced pressure
6. 6
   其他The solids were triturated with ether
7. 7
   过滤collected by filtration with an ether
8. 8
   洗涤rinse
9. 9
   其他then dried under nitrogen
10. 10
    workup.ADDITIONThis intermediate sulfinate salt was added to a well
11. 11
    workup.STIRRINGstirred
12. 12
    workup.ADDITIONmixture of 350 mL water and 250 mL dichloromethane
13. 13
    温度chilled to 0° C
14. 14
    workup.ADDITIONN-Chlorosuccinimide was then added in portions so as
15. 15
    其他the temperature below 3° C
16. 16
    workup.STIRRINGThe mixture was stirred vigorously for 30 min at ambient temperature
17. 17
    其他after which time, the layers were separated
18. 18
    洗涤the organic layer was washed successively with 10% aq NaHSO3, twice with aq NaHCO3
19. 19
    干燥dried (MgSO4)
20. 20
    过滤filtered
21. 21
    温度This dichloromethane solution was then cooled to 0° C.
22. 22
    workup.ADDITIONwas added over 2 min
23. 23
    workup.STIRRINGAfter stirring for 1 h at ambient temperature
24. 24
    其他solids had precipitated from the brown solution which
25. 25
    workup.WAITwas then left
26. 26
    workup.STIRRINGstirring for 3 days
27. 27
    workup.ADDITIONThe mixture was diluted with more dichloromethane
28. 28
    洗涤then washed three times with 1N HCl
29. 29
    干燥once with saturated aq NaCl, dried (MgSO4)
30. 30
    其他evaporated
31. 31
    其他The resulting solid residue was triturated
32. 32
    其他collected with a mixture of hexanes and n-chlorobutane

实验过程

A solution of 10 g (0.12 mol) of N-methyl-pyrrole in 120 mL of anhydrous THF under nitrogen atmosphere was cooled to below -70° C. then treated with 56 mL of 2.4M n-butyllithium in hexanes (0.13 mol) dropwise at such a rate as to keep the temperature below -60° C. The resulting brown colored mixture was stirred for 16 h at ambient temperature, then recooled to below -70° C. at which time liquified sulfur dioxide (9.0 mL, 0.21 mol) was added rapidly, causing an exotherm at -20° C. and the formation of a thick golden colored precipitate. After stirring for 1 h at ambient temperature, the THF was removed under reduced pressure. The solids were triturated with ether and collected by filtration with an ether rinse then dried under nitrogen. This intermediate sulfinate salt was added to a well stirred mixture of 350 mL water and 250 mL dichloromethane chilled to 0° C. N-Chlorosuccinimide was then added in portions so as to keep the temperature below 3° C. The mixture was stirred vigorously for 30 min at ambient temperature, after which time, the layers were separated and the organic layer was washed successively with 10% aq NaHSO3, twice with aq NaHCO3, dried (MgSO4) and filtered. This dichloromethane solution was then cooled to 0° C. and stirred while 82 mL (0.30 mol) of t-butylamine was added over 2 min. After stirring for 1 h at ambient temperature, solids had precipitated from the brown solution which was then left stirring for 3 days. The mixture was diluted with more dichloromethane then washed three times with 1N HCl, once with saturated aq NaCl, dried (MgSO4) and evaporated. The resulting solid residue was triturated and collected with a mixture of hexanes and n-chlorobutane to afford 7.4 g of the title compound as tan crystals, m.p. 125°-126° C.

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