Реакция #912

Уравнение реакции

HCl

n-butyllithium

N-(1,1-dimethylethyl)-1-methyl-1H-pyrrole-3-sulfonamide

dimethyldisulfide

→

title compound

Выход 58.8%

N-(1,1-Dimethylethyl)-1-methyl-2-(methylthio)-1H-pyrrole-3-sulfonamide

Выход 58.8%

Растворители

—

hexanes

THF

Условия реакции

Обработка

1. 1
   workup.ADDITIONwas added dropwise at such a rate as
2. 2
   Другоеthe temperature below -65° C
3. 3
   Другоеthe resulting reaction mixture
4. 4
   Температураto warm to room temperature
5. 5
   workup.STIRRINGstir for ca. 1.5 hours
6. 6
   ТемператураThe reaction mixture was cooled to 0° C.
7. 7
   ДругоеThe THF phase was separated
8. 8
   Промывкаwashed with brine
9. 9
   Сушкаdried (MgSO4)
10. 10
    Концентрированиеconcentrated in vacuo
11. 11
    ДругоеThe crude residue was chromatographed on silica (20% ethyl acetate/80% hexanes)

Методика

To a solution of 6.48 g (30 mmol) of N-(1,1-dimethylethyl)-1-methyl-1H-pyrrole-3-sulfonamide in 150 mL THF under nitrogen atmosphere cooled to -78° C. was added dropwise at such a rate as to keep the temperature below -65° C. 25.52 mL (61.5 mmol) 2.41M n-butyllithium in hexanes. The reaction was stirred at -78° C. for ca. 30 minutes. To the reaction mixture was added 2.97 mL (33 mmol) of dimethyldisulfide in one portion and the resulting reaction mixture was allowed to warm to room temperature and stir for ca. 1.5 hours. The reaction mixture was cooled to 0° C. and acidified with 1N HCl. The THF phase was separated washed with brine, dried (MgSO4) and concentrated in vacuo. The crude residue was chromatographed on silica (20% ethyl acetate/80% hexanes) affording 4.63 g of the title compound as an off white solid, m.p. 116°-119° C.

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