Toluene → ethyl 4-(4-chloro-9-oxo-9H-fluorene-2-yloxy)butyrate

Participants

Reaction Conditions

Reaction Steps

4-Chloro-2-hydroxy-9H-fluoren-9-one (48.6 g) was dissolved in N,N-dimethylformamide (150 ml), potassium carbonate (58.3 g) and ethyl 4-bromobutyrate (33.5 ml) were added, and the mixture was stirred at 60° C. for 2 hr. The reaction mixture was cooled to 40° C., and toluene (300 ml) and water (300 ml) were added to allow for layer separation. The obtained aqueous layer was extracted again with toluene (100 ml). The obtained organic layers were combined, washed twice with water (100 ml), anhydrous sodium sulfate and activated carbon (2.5 g) were added, and the mixture was stirred at room temperature for 5 min. The insoluble material was filtered off through celite, and the solvent in the filtrate was evaporated. To the obtained residue was added hexane (220 ml), and the mixture was stirred at 50° C. for 10 min and at room temperature for 1 hr. The precipitated solid was collected by filtration, and washed with hexane. The obtained solid was dried under reduced pressure to give the title compound (66.9 g). In addition, the solvent in the obtained filtrate was evaporated, to the residue were added ethyl acetate (5 ml) and hexane (20 ml), and the mixture was stirred at room temperature for 1 hr. The precipitated solid was collected by filtration, and washed with hexane. The obtained solid was dried under reduced pressure to further give the title compound (2.5 g).

Provenance & Evidence