Toluene → 2-Bromo-9,9-diethylfluorene

Beteiligte Stoffe

Reaktionsbedingungen

Reaktionsschritte

To a solution of 2-bromofluorene (2.5 g, 10 mmol) in toluene (40 ml) was added tetrabutylammonium bromide (0.8 g, 2.48 mmol) as a phase transfer catalyst. A freshly prepared solution of aqueous sodium hydroxide (25 ml, 50% w/w) was added at once to the solution. The mixture turned orange and became viscous. To this solution, iodoethane (2.4 ml, 30 mmol) was added. The mixture was stirred at 60° C. for a period of 8 h. It was diluted with ethyl acetate (25 ml) and washed several portions of water. Organic layer was dried over magnesium sulfate and concentrated in vacuuo to afford the crude product liquid. The products were purified by column chromatography (silica gel, hexane as eluent, Rf=0.8 on thin layer chromatography) giving colorless oil of 2-bromo-9,9-diethylfluorene (2.5 g) in a yield of 82%.

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