Dimethylformamide → 2-Bromo-9,9-dimethoxyethylfluorene

Beteiligte Stoffe

Reaktionsbedingungen

Reaktionsschritte

To a solution of 2-bromofluorene (2.0 g, 8.2 mmol) in dimethylformamide (dry, 30 ml) was added potassium t-butoxide (2.74 g, 24.4 mmol), giving a deep orange in color. The mixture was stirred at 45° C. for 20 min and added 2-bromoethylmethyl ether (3.5 g, 2.5 mmol) dropwise. Stirring was continued at the same temperature for overnight to give an orange solution. Another portion of 2-bromoethylmethyl ether (1.4 g, 1.0 mmol) was added and the mixture stirred at 80° C. for 4 h. It was diluted with water (100 ml). The products extracted with ethylacetate (20 ml) and washed with water. Organic layer was dried over magnesium sulfate and concentrated in vacuuo to afford the crude product. It was purified by preparative thin layer chromatography (silica gel, Rf=0.3 using hexane-EtOAc/3:2 as eluent) to give 2-bromo-9,9-dimethoxyethylfluorene (1.5 g).

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