反应 #909

反应方程式

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

Methyl chloroformate

HCl

n-butyllithium

→

title compound

Methyl 3-[[(1,1-dimethylethyl)amino]sulfonyl]-1-methyl-1H-pyrrole-2-carboxylate

溶剂

THF

—

hexanes

反应条件

后处理

1. 1
   workup.ADDITIONwas added dropwise at such a rate as
2. 2
   其他the temperature below -65° C
3. 3
   温度to warm to room temperature
4. 4
   workup.STIRRINGstirred for ca. 1.5 hours
5. 5
   温度was cooled to 0° C.
6. 6
   其他The THF phase was separated
7. 7
   洗涤washed with brine
8. 8
   干燥dried (MgSO4)
9. 9
   浓缩concentrated to an ember oil
10. 10
    其他The NMR of the crude reaction product

实验过程

To a solution of I g (4.62 mol) of N-(1,1-dimethylethyl)-1-methyl-1H-pyrrole-3-sulfonamide in 150 mL THF under a nitrogen atmosphere cooled to -78° C. was added dropwise at such a rate as to keep the temperature below -65° C. 4.1 mL (9.48 mmol) 2.32M n-butyllithium in hexanes. The resulting amber turbid solution was stirred at -78° C. for ca. 30 minutes. Methyl chloroformate (0.37 mL, 4.86 mmol) was added in one portion and the resulting gold reaction mixture was allowed to warm to room temperature and stirred for ca. 1.5 hours. The gold reaction mixture was cooled to 0° C. and acidified with 1N HCl. The THF phase was separated washed with brine, dried (MgSO4) and concentrated to an ember oil. The NMR of the crude reaction product was consistent with the title compound, additionally the NMR indicated that a trace of the starting material was also present. The crude material was combined with the product from a similar reaction run on the scale described below and chromatographed to give the title compound.

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