ethyl 3,5-dioxocyclohexane-1-carboxylate

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: 4.2 g of ethyl 3,5-dioxocyclohexanecarboxylate and 3.4 g of triethylamine were dissolved in 50 ml of dichloromethane, to which was added dropwise 2.9 g of propionyl chloride under stirring at room temperature. The resultant mixture was allowed to react at ambient temperature for 2 hours, after which the reaction solution was washed with water and admixed with a dilute aqueous sodium bicarbonate solution to remove the acidic matters from the reaction solution. The organic layer was then separated from the aqueous phase, dried and concentrated to a small volume. The concentrated solution was taken up in 20 ml of toluene, followed by addition of 0.5 g of 4-N,N-dimethylaminopyridine and heating the mixture at 85° C. for 3 hours. Thereafter, the toluene was removed from the reaction solution by distillation under reduced pressure, and the residue was chromatographed on silica gel using benzene as developing solvent to afford 2.5 g of the title compound (Compound No. 9 of Table 1) as colorless flakes having a melting point of 55°- 56° C. to react at ambient temperature for 2 hours after which the reaction solution was washed with water to remove the acidic matters from the reaction solution The organic layer was then separated from the aqueous phase dried concentrated to a small volume followed by addition of 0.5 g of 4-N,N-dimethylaminopyridine heating the mixture at 85° C. for 3 hours Thereafter, the toluene was removed from the reaction solution by distillation under reduced pressure the residue was chromatographed on silica gel

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

Procedure: 4.2 g of ethyl 3,5-dioxocyclohexanecarboxylate and 3.4 g of triethylamine were dissolved in 50 ml of dichloromethane, to which was added dropwise 2.9 g of propionyl chloride under stirring at room temperature. The resultant mixture was allowed to react at ambient temperature for 2 hours, after which the reaction solution was washed with water and admixed with a dilute aqueous sodium bicarbonate solution to remove the acidic matters from the reaction solution. The organic layer was then separated from the aqueous phase, dried and concentrated to a small volume. The concentrated solution was taken up in 20 ml of toluene, followed by addition of 0.5 g of 4-N,N-dimethylaminopyridine and heating the mixture at 85° C. for 3 hours. Thereafter, the toluene was removed from the reaction solution by distillation under reduced pressure, and the residue was chromatographed on silica gel using benzene as developing solvent to afford 2.5 g of the title compound (Compound No. 9 of Table 1) as colorless flakes having a melting point of 55°- 56° C. to react at ambient temperature for 2 hours after which the reaction solution was washed with water to remove the acidic matters from the reaction solution The organic layer was then separated from the aqueous phase dried concentrated to a small volume followed by addition of 0.5 g of 4-N,N-dimethylaminopyridine heating the mixture at 85° C. for 3 hours Thereafter, the toluene was removed from the reaction solution by distillation under reduced pressure the residue was chromatographed on silica gel

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

Procedure: To 150 ml of ethanol containing 3.4 g of sodium was added dropwise 31 g of diethyl acetonylsuccinate (or diethyl acetmethylsuccinate) over about one hour with stirring at ambient temperature. The mixture was heated under reflux for 2 hours and then cooled to room temperature, followed by distillation off of the ethanol under reduced pressure. There was thus obtained a brown viscous liquid comprising sodium salt of ethyl 3,5-dioxocyclohexanecarboxylate as formed, to which were added 100 ml of toluene, 50 ml of ice water and 0.3 g of γ-picoline and then added dropwise 15 g of n-butyryl chloride at ambient temperature under agitation over about 2 hours. The resultant reaction mixture was agitated for further 30 minutes and then the toluene layer was separated, washed with water, dried and admixed with 0.8 g of 4-N,N-dimethylaminopyridine. The admixture was heated with agitation at a temperature of 80°-90° C. for 3 hours. The toluene was then distilled off from the reaction solution under reduced pressure and the residue was chromatographed on a column of silica gel developed with benzene to give 19.5 g (55.9%) of the object compound (Compound No. 15). The mixture was heated under reflux for 2 hours cooled to room temperature followed by distillation off of the ethanol under reduced pressure

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

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

Procedure: 7.75 g (55.1 mmol) Benzoyl chloride was added dropwise to 10.00 g (54.3 mmol) ethyl 3,5-dioxocyclohexanecarboxylate, dissolved in 100 ml dichloromethane and 15 ml triethylamine, at 10° C. The mixture was stirred for 3 hours at room temperature, poured into ice, separated, the organic phase shaken with 1N hydrochloric acid, saturated sodium bicarbonate and water, dried (magnesium sulphate) and concentrated. The ethyl 3-benzoyloxy-5-oxo-3-cyclohexenecarboxylate, so obtained, was dissolved in 75 ml acetonitrile and after addition of 15 ml triethylamine and 1.5 ml 2-hydroxyisobutyronitrile, was stirred at 24 hours at room temperature. The mixture was taken up in 100 ml diethyl ether and extracted with 100 ml 2N hydrochloric acid and then twice with, each time, 50 ml 5% potassium carbonate solution. After covering the aqueous phase with a layer of 100 ml diethyl ether, it was acidified with 4N hydrochloric acid until it was pH 3, separated, washed with water, dried (magnesium sulphate) and evaporated on a rotary evaporator. It was purified by recrystallising from hexane. at 10° C poured into ice separated the organic phase shaken with 1N hydrochloric acid, saturated sodium bicarbonate and water dried (magnesium sulphate) concentrated

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

Procedure: 4.2 g of ethyl 3,5-dioxocyclohexanecarboxylate and 3.4 g of triethylamine were dissolved in 50 ml of dichloromethane, to which was added dropwise 2.9 g of propionyl chloride under stirring at room temperature. The resultant mixture was allowed to react at ambient temperature for 2 hours, after which the reaction solution was washed with water and admixed with a dilute aqueous sodium bicarbonate solution to remove the acidic matters from the reaction solution. The organic layer was then separated from the aqueous phase, dried and concentrated to a small volume. The concentrated solution was taken up in 20 ml of toluene, followed by addition of 0.5 g of 4-N,N-dimethylaminopyridine and heating the mixture at 85° C. for 3 hours. Thereafter, the toluene was removed from the reaction solution by distillation under reduced pressure, and the residue was chromatographed on silica gel using benzene as developing solvent to afford 2.5 g of the title compound (Compound No. 9 of Table 1) as colorless flakes having a melting point of 55°- 56° C. to react at ambient temperature for 2 hours after which the reaction solution was washed with water to remove the acidic matters from the reaction solution The organic layer was then separated from the aqueous phase dried concentrated to a small volume followed by addition of 0.5 g of 4-N,N-dimethylaminopyridine heating the mixture at 85° C. for 3 hours Thereafter, the toluene was removed from the reaction solution by distillation under reduced pressure the residue was chromatographed on silica gel

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

Procedure: To 150 ml of ethanol containing 3.4 g of sodium was added dropwise 31 g of diethyl acetonylsuccinate (or diethyl acetmethylsuccinate) over about one hour with stirring at ambient temperature. The mixture was heated under reflux for 2 hours and then cooled to room temperature, followed by distillation off of the ethanol under reduced pressure. There was thus obtained a brown viscous liquid comprising sodium salt of ethyl 3,5-dioxocyclohexanecarboxylate as formed, to which were added 100 ml of toluene, 50 ml of ice water and 0.3 g of γ-picoline and then added dropwise 15 g of n-butyryl chloride at ambient temperature under agitation over about 2 hours. The resultant reaction mixture was agitated for further 30 minutes and then the toluene layer was separated, washed with water, dried and admixed with 0.8 g of 4-N,N-dimethylaminopyridine. The admixture was heated with agitation at a temperature of 80°-90° C. for 3 hours. The toluene was then distilled off from the reaction solution under reduced pressure and the residue was chromatographed on a column of silica gel developed with benzene to give 19.5 g (55.9%) of the object compound (Compound No. 15). The mixture was heated under reflux for 2 hours cooled to room temperature followed by distillation off of the ethanol under reduced pressure

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

Procedure: 4.2 g of ethyl 3,5-dioxocyclohexanecarboxylate and 3.4 g of triethylamine were dissolved in 50 ml of dichloromethane, to which was added dropwise 2.9 g of propionyl chloride under stirring at room temperature. The resultant mixture was allowed to react at ambient temperature for 2 hours, after which the reaction solution was washed with solution to remove the acidic matters from the reaction solution. The organic layer was then separated from the aqueous phase, dried and concentrated to a small volume. The concentrated solution was taken up in 20 ml of toluene, followed by addition of 0.5 g of 4-N,N-dimethylaminopyridine and heating the mixture at 85° C. for 3 hours. Thereafter, the toluene was removed from the reaction solution by distillation under reduced pressure, and the residue was chromatographed on silica gel using benzene as developing solvent to afford 2.5 g of the title compound (Compound No. 9 of Table 1) as colorless flakes having a melting point of 55°-56° C. to react at ambient temperature for 2 hours after which the reaction solution was washed with solution to remove the acidic matters from the reaction solution The organic layer was then separated from the aqueous phase dried concentrated to a small volume followed by addition of 0.5 g of 4-N,N-dimethylaminopyridine heating the mixture at 85° C. for 3 hours Thereafter, the toluene was removed from the reaction solution by distillation under reduced pressure the residue was chromatographed on silica gel

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

Procedure: To 150 ml of ethanol containing 3.4 g of sodium was added dropwise 31 g of diethyl acetonylsuccinate (or diethyl acetmethylsuccinate) over about one hour with stirring at ambient temperature. The mixture was heated under reflux for 2 hours and then cooled to room temperature, followed by distillation off of the ethanol under reduced pressure. There was thus obtained a brown viscous liquid comprising sodium salt of ethyl 3,5-dioxocyclohexanecarboxylate as formed, to which were added 100 ml of toluene, 50 ml of ice water and 0.3 g of γ-picoline and then added dropwise 15 g of n-butyryl chloride at ambient temperature under agitation over about 2 hours. The resultant reaction mixture was agitated for further 30 minutes and then the toluene layer was separated, washed with water, dried and admixed with 0.8 g of 4-N,N-dimethylaminopyridine. The admixture was heated with agitation at a temperature of 80°-90° C. for 3 hours. The toluene was then distilled off from the reaction solution under reduced pressure and the residue was chromatographed on a column of silica gel developed with benzene to give 19.5 g (55.9%) of the object compound (Compound No. 15). The mixture was heated under reflux for 2 hours cooled to room temperature followed by distillation off of the ethanol under reduced pressure

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

Procedure: 4.2 g of ethyl 3,5-dioxocyclohexanecarboxylate and 3.4 g of triethylamine were dissolved in 50 ml of dichloromethane, to which was added dropwise 2.9 g of propionyl chloride under stirring at room temperature. The resultant mixture was allowed to react at ambient temperature for 2 hours, after which the reaction solution was washed with water and admixed with a dilute aqueous sodium bicarbonate solution to remove the acidic matters from the reaction solution. The organic layer was then separated from the aqueous phase, dried and concentrated to a small volume. The concentrated solution was taken up in 20 ml of toluene, followed by addition of 0.5 g of 4-N,N-dimethylaminopyridine and heating the mixture at 85° C. for 3 hours. Thereafter, the toluene was removed from the reaction solution by distillation under reduced pressure, and the residue was chromatographed on silica gel using benzene as developing solvent to afford 2.5 g of the title compound (Compound No. 9 of Table 1) as colorless flakes having a melting point of 55°- 56° C. to react at ambient temperature for 2 hours after which the reaction solution was washed with water to remove the acidic matters from the reaction solution The organic layer was then separated from the aqueous phase dried concentrated to a small volume followed by addition of 0.5 g of 4-N,N-dimethylaminopyridine heating the mixture at 85° C. for 3 hours Thereafter, the toluene was removed from the reaction solution by distillation under reduced pressure the residue was chromatographed on silica gel