ethyl 4,4,5,5,5-pentafluoro-3-oxopentanoate

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: Ethyl acetate (20.26 g, 0.23 mole) and sodium metal (2.3 g, 0.10 g-atom) was added to ethyl pentafluoropropionate (20.26 g, 0.23 mole) and the mixture was refluxed with stirring until sodium metal was dissolved. After sodium metal was dissolved, dry diethyl ether (100 ml) was added and the solution was further reacted under reflux overnight. After completion of the reaction, the solvent was evaporated under reduced pressure and the resulting residue was made acidic with 50 ml of 15% sulfuric acid, while it was cool. The solution was extracted with diethyl ether and the ether layer was dried with anhydrous sodium sulfate. Diethyl ether was then distilled off by distilling at atmospheric pressure using a fractionating column packed with Raschig ring and the resulting residue was further distilled under reduced pressure to give 9.90 g (42.3%) of the title compound as a colorless liquid, b.p. 77°-78° C./80 mmHg. The structure of this compound was confirmed by IR and NMR. the mixture was refluxed was dissolved the solution was further reacted under reflux overnight After completion of the reaction the solvent was evaporated under reduced pressure was cool The solution was extracted with diethyl ether the ether layer was dried with anhydrous sodium sulfate Diethyl ether was then distilled off by distilling at atmospheric pressure the resulting residue was further distilled under reduced pressure

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

Procedure: Ethyl acetate (20.26 g, 0.23 mole) and sodium metal (2.3 g, 0.10 g-atom) was added to ethyl pentafluoropropionate (20.26 g, 0.23 mole) and the mixture was refluxed with stirring until sodium metal was dissolved. After sodium metal was dissolved, dry diethyl ether (100 ml) was added and the solution was further reacted under reflux overnight. After completion of the reaction, the solvent was evaporated under reduced pressure and the resulting residue was made acidic with 50 ml of 15% sulfuric acid, while it was cool. The solution was extracted with diethyl ether and the ether layer was dried with anhydrous sodium sulfate. Diethyl ether was then distilled off by distilling at atmospheric pressure using a fractionating column packed with Raschig ring and the resulting residue was further distilled under reduced pressure to give 9.90 g (42.3%) of the title compound as a colorless liquid, b.p. 77°-78° C./80 mmHg. The structure of this compound was confirmed by IR and NMR. the mixture was refluxed was dissolved the solution was further reacted under reflux overnight After completion of the reaction the solvent was evaporated under reduced pressure was cool The solution was extracted with diethyl ether the ether layer was dried with anhydrous sodium sulfate Diethyl ether was then distilled off by distilling at atmospheric pressure the resulting residue was further distilled under reduced pressure

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

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

Conditions: temp:120.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: A suspension of acrylamide (4.11 g), ethyl 4,4,5,5,5-pentafluoro-3-oxopentanoate (16.5 g) and p-toluenesulphonic acid (0.120 g) in chlorobenzene (40 mL) was sonicated for 30 minutes then heated by microwave irradiation (150 W, 120° C.) for 3 h. The reaction mixture was concentrated in vacuo and subjected to flash column chromatography (eluent 1:3 ethyl acetate/isohexane) to yield a colourless solid (0.697 g). was sonicated for 30 minutes The reaction mixture was concentrated in vacuo

Conditions: temp:120.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: A suspension of acrylamide (4.11 g), ethyl 4,4,5,5,5-pentafluoro-3-oxopentanoate (16.5 g) and p-toluenesulphonic acid (0.120 g) in chlorobenzene (40 mL) was sonicated for 30 minutes then heated by microwave irradiation (150 W, 120° C.) for 3 h. The reaction mixture was concentrated in vacuo and subjected to flash column chromatography (eluent 1:3 ethyl acetate/isohexane) to yield a colourless solid (0.697 g). was sonicated for 30 minutes The reaction mixture was concentrated in vacuo

Conditions: temp:0.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: A solution of KCN (1.4 eq.) in water (0.5 M) was added with stirring to an ice-cooled solution of ethyl 4,4,5,5,5-pentafluoro-3-oxopentanoate (1 eq.) in EtOH and water (40:60 vol). The mixture was stirred for 6 h at 0° C. and then acidified with 6N sulphuric acid and extracted with Et2O. The organic phase was dried (Na2SO4), and the solvents were removed under reduced pressure. The residue was vacuum distilled. The product fraction was collected at 74-76° C./0.5 mbar. (400 MHz, CDCl3) δ: 5.88 (1H, s), 4.40-4.23 (2H, m), 3.04 (1H, s), 1.33 (3H, t, J=7.1 Hz). extracted with Et2O The organic phase was dried (Na2SO4) the solvents were removed under reduced pressure distilled The product fraction was collected at 74-76° C./0.5 mbar

Conditions: temp:0.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: A solution of KCN (1.4 eq.) in water (0.5 M) was added with stirring to an ice-cooled solution of ethyl 4,4,5,5,5-pentafluoro-3-oxopentanoate (1 eq.) in EtOH and water (40:60 vol). The mixture was stirred for 6 h at 0° C. and then acidified with 6N sulphuric acid and extracted with Et2O. The organic phase was dried (Na2SO4), and the solvents were removed under reduced pressure. The residue was vacuum distilled. The product fraction was collected at 74-76° C./0.5 mbar. (400 MHz, CDCl3) δ: 5.88 (1H, s), 4.40-4.23 (2H, m), 3.04 (1H, s), 1.33 (3H, t, J=7.1 Hz). extracted with Et2O The organic phase was dried (Na2SO4) the solvents were removed under reduced pressure distilled The product fraction was collected at 74-76° C./0.5 mbar

Conditions: temp:135.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: A sealable vial was charged with triethylorthoformate (1.07 mL, 6.41 mmol), acetic anhydride (3.22 mL, 34.2 mmol) and ethyl 4,4,5,5,5-pentafluoro-3-oxopentanoate (0.747 mL, 4.27 mmol), and the resulting mixture was capped and stirred at 135° C. After 2 h, the reaction mixture was allowed to cool to room temperature, and the volatiles were removed in vacuo to provide the title compound as a mixture of olefin isomers, which was used without further purification. the resulting mixture was capped to cool to room temperature the volatiles were removed in vacuo

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

Procedure: A solution of Na (2.3 g, 0.1 mol) in EtOH (125 mL) was mixed with acetamidine hydrochloride (4.72 g, 50 mmol) and the reaction mixture was stirred for 15 min. Ethyl pentafluoropropionylacetate (11.7 g, 50 mmol) was added and the reaction mixture was refluxed for 6 h. The solvent was removed in vacuo, and the residue was taken up in H2O and acidified with dilute HCl to pH 2. The aqueous solution was extracted with EtOAc and the organic layer was dried over Na2SO4, then evaporated to afford 6 g of a yellowish solid. The crude product was purified by flash chromatography (CHCl3 containing MeOH 0% to 4%) to provide 2 g (17.5% yield) of a solid. the reaction mixture was refluxed for 6 h The solvent was removed in vacuo The aqueous solution was extracted with EtOAc the organic layer was dried over Na2SO4 evaporated