Reaktion #430435

Reaktionsgleichung

4-bromoiodobenzene

2,3-difluro-4-octoxyphenylboronic acid

4-bromoiodobenzene

sodium carbonate

→

4'-bromo-2.3-difluoro-4-octoxybiphenyl

Lösungsmittel

dimethoxyethane

dimethoxyethane

Reaktionsbedingungen

Aufarbeitung

1. 1
   TemperaturThe stirred mixture was refluxed gently
2. 2
   Sonstigehad reacted completely (usually 4-5hr)
3. 3
   SonstigeThe layers were separated
4. 4
   Extraktionthe aqueous layer once more extracted with ether
5. 5
   WaschenThe combined organic layers were washed with brine
6. 6
   Trocknendried (MgSO4)
7. 7
   SonstigeThe solvent was removed in vacuo
8. 8
   Sonstigethe residue purified by column chromatography (silica gel/petroleum fraction (bp 40°-60° C.) - ethyl acetate, 9:1)
9. 9
   Sonstigeto give a white solid which
10. 10
    Sonstigewas recrystallised from pentane (-20° C.)
11. 11
    Sonstigeto yield colourless crystals

Vorschrift

A solution of 2,3-difluro-4-octoxyphenylboronic acid (5) (8.29 g, 0.029 mol) in dimethoxyethane (40 ml) was added to a solution of 4-bromoiodobenzene (6.80 g, 0.024 mol) and tetrakis(triphenylphosphine)palladium (0) (1.4 8 g. 1.29 mmol) in dimethoxyethane (40 ml) under nitrogen. To this, 2M sodium carbonate (60 ml) was added. The stirred mixture was refluxed gently. Progress of the reaction was carefully monitored using tic until the 4-bromoiodobenzene had reacted completely (usually 4-5hr). The layers were separated and the aqueous layer once more extracted with ether. The combined organic layers were washed with brine and dried (MgSO4). The solvent was removed in vacuo and the residue purified by column chromatography (silica gel/petroleum fraction (bp 40°-60° C.) - ethyl acetate, 9:1) to give a white solid which was recrystallised from pentane (-20° C.) to yield colourless crystals.

Quelle