反応 #916

反応方程式

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

N,N-dimethylformamide

HCl

→

title compound

収率 39.0%

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

収率 39.0%

溶媒

THF

—

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
   温度The reaction mixture was cooled to 0° C.
5. 5
   その他The THF phase was separated
6. 6
   洗浄washed with brine
7. 7
   乾燥dried (MgSO4)
8. 8
   濃縮concentrated in vacuo
9. 9
   その他The crude residue was chromatographed on silica (25% ethyl acetate/80% hexanes)

実験手順

To a solution of 12.96 g (60 mmol) of N-(1,1-dimethylethyl)-1-methyl-1H-pyrrole-3-sulfonamide in 300 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., 52.35 mL (123 mmol) 2.35M n-butylithium in hexanes. The reaction was stirred at -78° C. for ca. 30 minutes. To the reaction mixture was added 4.64 mL (60 mmol) of N,N-dimethylformamide dropwise. The reaction mixture was allowed to warm to room temperature and stir for ca. 2 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 (25% ethyl acetate/80% hexanes) affording 5.72 g of the title compound as a white solid, m.p. 101.5°-103° C.

出典