1-(4-fluorophenyl)butane-1,3-dione

Conditions: temp:0.00; pressure:0.00; stir:

Conditions: temp:0.00; pressure:0.00; stir:

Conditions: temp:0.00; pressure:0.00; stir:

Conditions: temp:0.00; pressure:0.00; stir:

Conditions: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: To a solution of L-tyrosine methyl ester (4.00 g, 20.51 mmol) in methanol (150 ml) is added 1-(4-fluorobenzoyl)acetone (4.06 g, 22.56 mmol), then the mixture is heated to reflux for 24 h. The solvent is evaporated under a vacuum. To the residue is added ethanol (50 ml), then the ethanol is distilled off under atmospheric pressure. The crude product is purified by silica gel chromatography using hexane/EtOAc (4:1) as eluent to give the title compound (7.03 g, 96%). the mixture is heated to reflux for 24 h The solvent is evaporated under a vacuum To the residue is added ethanol (50 ml) the ethanol is distilled off under atmospheric pressure The crude product is purified by silica gel chromatography

Conditions: temp:100.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: A mixture of 1-(4-fluorophenyl)butane-1,3-dione (1.0 g), potassium carbonate (3.84 g), and tetrabutylammonium bromide (90 mg) in toluene (20 ml) was refluxed for 3 hours, then ethyl 6-bromohexanoate (1.18 ml) was added. After stirring at 100° C. for 3 hours, the mixture was partitoned between ethyl acetate and 0.5N hydrochloric acid. The organic layer was separated, washed with water and brine, dried over magnesium sulfate, and evaporated. The residue was chromatographed on silica gel eluting with a mixture of ethyl acetate and hexane (1:5) to give ethyl 7-(4-fluorobenzoyl)-8-oxononanoate (983 mg) as an oil. was refluxed for 3 hours The organic layer was separated washed with water and brine dried over magnesium sulfate evaporated The residue was chromatographed on silica gel eluting with a mixture of ethyl acetate and hexane (1:5)

Conditions: temp:100.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: A mixture of 1-(4-fluorophenyl)butane-1,3-dione (1.0 g), potassium carbonate (3.84 g), and tetrabutylammonium bromide (90 mg) in toluene (20 ml) was refluxed for 3 hours, then ethyl 6-bromohexanoate (1.18 ml) was added. After stirring at 100° C. for 3 hours, the mixture was partitoned between ethyl acetate and 0.5N hydrochloric acid. The organic layer was separated, washed with water and brine, dried over magnesium sulfate, and evaporated. The residue was chromatographed on silica gel eluting with a mixture of ethyl acetate and hexane (1:5) to give ethyl 7-(4-fluorobenzoyl)-8-oxononanoate (983 mg) as an oil. was refluxed for 3 hours The organic layer was separated washed with water and brine dried over magnesium sulfate evaporated The residue was chromatographed on silica gel eluting with a mixture of ethyl acetate and hexane (1:5)

Conditions: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: A mixture of 5 g of 4-fluorobenzoylacetone, 1.66 g of urea, 25 ml of ethanol, and 3.8 ml of concentrated hydrochloric acid was refluxed for 20 hours. This reaction mixture was cooled, poured into iced water, made basic with aqueous solution of potassium carbonate, and neutralized with acetic acid. The crystals that separated out were collected by filtration, washed with isopropyl ether, and dried to provide 2.65 g of pale yellow crystals. m.p. 265-268° C. was refluxed for 20 hours This reaction mixture was cooled The crystals that separated out were collected by filtration washed with isopropyl ether dried

Conditions: temp:0.00; pressure:0.00; stir:

Conditions: temp:0.00; pressure:0.00; stir:

Conditions: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: To a solution of L-tyrosine methyl ester (4.00 g, 20.51 mmol) in methanol (150 ml) is added 1-(4-fluorobenzoyl)acetone (4.06 g, 22.56 mmol), then the mixture is heated to reflux for 24 h. The solvent is evaporated under a vacuum. To the residue is added ethanol (50 ml), then the ethanol is distilled off under atmospheric pressure. The crude product is purified by silica gel chromatography using hexane/EtOAc (4:1) as eluent to give the title compound (7.03 g, 96%). the mixture is heated to reflux for 24 h The solvent is evaporated under a vacuum To the residue is added ethanol (50 ml) the ethanol is distilled off under atmospheric pressure The crude product is purified by silica gel chromatography

Conditions: temp:0.00; pressure:0.00; stir: