Reaktion #914

ord-0d425205828e434aa8465064fdc60f2d

Reaktionsgleichung

Cl
HCl
Cn1ccc(S(=O)(=O)NC(C)(C)C)c1
N-(1,1-dimethylethyl)-1-methyl-1H-pyrrole-3-sulfonamide
[Li][CH2]CCC
n-butyllithium
BrBr
bromine
Cn1ccc(S(=O)(=O)NC(C)(C)C)c1Br
title compound
Ausbeute 58.7%
Cn1ccc(S(=O)(=O)NC(C)(C)C)c1Br
2-Bromo-N-(1,1-dimethylethyl)-1-methyl-1H-pyrrole-3-sulfonamide
Ausbeute 58.7%

Reaktionsbedingungen

Temperatur
-78°CELSIUS
Detaillierte Bedingungen
See reaction.notes.procedure_details.

Aufarbeitung

  1. 1
    workup.ADDITIONwas added dropwise
  2. 2
    Temperaturto warm to room temperature
  3. 3
    workup.STIRRINGstir for ca. 2 hours
  4. 4
    workup.STIRRINGstirred at room temperature
  5. 5
    TemperaturThe reaction mixture was cooled to 0° C.
  6. 6
    SonstigeThe ether phase was separated
  7. 7
    Waschenwashed with brine
  8. 8
    Trocknendried (MgSO4)
  9. 9
    Einengenconcentrated in vacuo
  10. 10
    SonstigeThe crude residue was chromatographed on silica (25% ethyl acetate/80% hexanes)

Vorschrift

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.

Quelle

DOI: 10.6084/m9.figshare.5104873.v1Patent: US05723410uspto-grants-1998_03