反応 #914

反応方程式

HCl

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

n-butyllithium

bromine

→

title compound

収率 58.7%

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

収率 58.7%

溶媒

diethyl ether

—

hexanes

反応条件

後処理

1. 1
   workup.ADDITIONwas added dropwise
2. 2
   温度to warm to room temperature
3. 3
   workup.STIRRINGstir for ca. 2 hours
4. 4
   workup.STIRRINGstirred at room temperature
5. 5
   温度The reaction mixture was cooled to 0° C.
6. 6
   その他The ether phase was separated
7. 7
   洗浄washed with brine
8. 8
   乾燥dried (MgSO4)
9. 9
   濃縮concentrated in vacuo
10. 10
    その他The crude residue was chromatographed on silica (25% ethyl acetate/80% hexanes)

実験手順

To a solution of 8.85 g (41 mmol) of N-(1,1-dimethylethyl)-1-methyl-1H-pyrrole-3-sulfonamide in 200 mL diethyl ether under a nitrogen atmosphere cooled to -78° C. was added dropwise, at such a rate as to keep the temperature below -65° C., 36.0 mL (85 mmol) 2.41M n-butyllithium in hexanes. The reaction was stirred at -78° C. for ca. 15 minutes. To the reaction mixture was added 2.2 mL (41 mmol) of bromine dropwise. The light orange reaction mixture was allowed to warm to room temperature and stir for ca. 2 hours. The reaction mixture darkened as it stirred at room temperature. The reaction mixture was cooled to 0° C. and acidified with 1N HCl. The ether phase was separated, washed with brine, dried (MgSO4) and concentrated in vacuo. The crude residue was chromatographed on silica (25% ethyl acetate/80% hexanes) affording 7.11 g of the title compound as an orange oil.

出典