ethyl 4-fluoro-3-oxobutanoate

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

Procedure: Ethyl 4-fluoro-3-oxobutanoate (2.1 g) was heated at reflux in 2-methoxyethanol (10 ml) for 3 hours. The solvent was removed in vacuo and the residue distilled to give the title compound as a colourless oil (1.75 g). Nmr (CDCl3)δ4.9 (d,2H,J-48 Hz), 3.4 (s,3H). The solvent was removed in vacuo the residue distilled

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

Procedure: 3-Nitrobenzaldehyde (1.51 g, 10 mmoles), ethyl 4-fluoro-3-oxo-butanoate (3 g, 20 mmoles) and aqueous ammonia (1.1 ml, d=0.88) in ethanol (15 ml) were heated at reflux for 14 hours more aqueous ammonia (0.55 ml) was added after 6 hours. The solvent was removed in vacuo and the residue was chromatographed on silica eluting with ether/petroleum ether (60°-80°) mixtures and the product obtained was recrystallised from 2-propanol to give the title compound as yellow crystals (0.4 g) mp 113°-4°. was added after 6 hours The solvent was removed in vacuo the residue was chromatographed on silica eluting with ether/petroleum ether (60°-80°) mixtures the product obtained was recrystallised from 2-propanol

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

Procedure: Ethyl 4-fluoro-3-oxobutanoate (2.1 g) was heated at reflux in 2-methoxyethanol (10 ml) for 3 hours. The solvent was removed in vacuo and the residue distilled to give the title compound as a colourless oil (1.75 g). Nmr (CDCl3)δ4.9 (d,2H,J-48 Hz), 3.4 (s,3H). The solvent was removed in vacuo the residue distilled

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

Procedure: 3-Nitrobenzaldehyde (1.51 g, 10 mmoles), ethyl 4-fluoro-3-oxo-butanoate (3 g, 20 mmoles) and aqueous ammonia (1.1 ml, d=0.88) in ethanol (15 ml) were heated at reflux for 14 hours more aqueous ammonia (0.55 ml) was added after 6 hours. The solvent was removed in vacuo and the residue was chromatographed on silica eluting with ether/petroleum ether (60°-80°) mixtures and the product obtained was recrystallised from 2-propanol to give the title compound as yellow crystals (0.4 g) mp 113°-4°. was added after 6 hours The solvent was removed in vacuo the residue was chromatographed on silica eluting with ether/petroleum ether (60°-80°) mixtures the product obtained was recrystallised from 2-propanol

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

Procedure: 3-Nitrobenzaldehyde (1.51 g, 10 mmoles), ethyl 4-fluoro-3-oxo-butanoate (3 g, 20 mmoles) and aqueous ammonia (1.1 ml, d=0.88) in ethanol (15 ml) were heated at reflux for 14 hours more aqueous ammonia (0.55 ml) was added after 6 hours. The solvent was removed in vacuo and the residue was chromatographed on silica eluting with ether/petroleum ether (60°-80°) mixtures and the product obtained was recrystallised from 2-propanol to give the title compound as yellow crystals (0.4 g) mp 113°-4°. was added after 6 hours The solvent was removed in vacuo the residue was chromatographed on silica eluting with ether/petroleum ether (60°-80°) mixtures the product obtained was recrystallised from 2-propanol

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

Procedure: Ethyl 4-fluoro-3-oxobutanoate (2.1 g) was heated at reflux in 2-methoxyethanol (10 ml) for 3 hours. The solvent was removed in vacuo and the residue distilled to give the title compound as a colourless oil (1.75 g). Nmr (CDCl3)δ4.9 (d,2H,J-48 Hz), 3.4 (s,3H). The solvent was removed in vacuo the residue distilled

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

Procedure: Ethyl 4-fluoro-3-oxobutanoate (1.45 g, 10 mmoles), ethyl 2-(3-nitrophenylmethylene)-3-oxobutanoate (2.63 g, 10 mmoles) and aqueous ammonia (1.1 ml, d 0.88) were heated at reflux in ethanol (15 ml) for 6 hours. The solvent was removed in vacuo and the residue purified by chromatography on silica eluting with petroleum ether (60°-80° )/ether mixtures. Recrystallisation from ether/petroleum ether (60°-80° ) gave the title compound (1.1 g) as yellow crystals mp 139°-41°. The solvent was removed in vacuo the residue purified by chromatography on silica eluting with petroleum ether (60°-80° )/ether mixtures Recrystallisation from ether/petroleum ether (60°-80° )

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

Procedure: Ethyl 4-fluoro-3-oxobutanoate (2.1 g) was heated at reflux in 2-methoxyethanol (10 ml) for 3 hours. The solvent was removed in vacuo and the residue distilled to give the title compound as a colourless oil (1.75 g). Nmr (CDCl3)δ4.9 (d,2H,J-48 Hz), 3.4 (s,3H). The solvent was removed in vacuo the residue distilled

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

Procedure: 3-Nitrobenzaldehyde (1.51 g, 10 mmoles), ethyl 4-fluoro-3-oxo-butanoate (3 g, 20 mmoles) and aqueous ammonia (1.1 ml, d=0.88) in ethanol (15 ml) were heated at reflux for 14 hours more aqueous ammonia (0.55 ml) was added after 6 hours. The solvent was removed in vacuo and the residue was chromatographed on silica eluting with ether/petroleum ether (60°-80°) mixtures and the product obtained was recrystallised from 2-propanol to give the title compound as yellow crystals (0.4 g) mp 113°-4°. was added after 6 hours The solvent was removed in vacuo the residue was chromatographed on silica eluting with ether/petroleum ether (60°-80°) mixtures the product obtained was recrystallised from 2-propanol