2,4-dioxopentan-3-yl benzoate

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: A flask was charged with 2,4-dioxopentan-3-yl benzoate (82.59 g, 375.0 mmol) and ethanol (1.5 L) was added. To this solution was added methylhydrazine (39.90 ml, 750.1 mmol) in ethanol (150 mL). The reaction was stirred at ambient temperature for 2 hours and concentrated in vacuo to afford 1,3,5-trimethyl-1H-pyrazol-4-yl benzoate (80 g, 92.6% yield). was added concentrated in vacuo

Conditions: temp:50.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: A flask was charged with powdered potassium hydroxide (21.89 g, 390.2 mmol), benzoic acid (47.65 g, 390.2 mmol), and DMF (500 mL). The mixture was heated at 50° C. for 1 hour. 3-Chloropentane-2,4-dione (52.5 g, 390.2 mmol) was added and the reaction was stirred 50° C. overnight. The reaction was cooled to ambient temperature, diluted in water (1.5 L) and extracted with ether (3×500 mL). The combined organic layers were washed with water, saturated NH4Cl and brine. The organic layer was dried over sodium sulfate and concentrated in vacuo to afford 2,4-dioxopentan-3-yl benzoate (82.59 g, 96.12% yield) as yellow oil. The reaction was cooled to ambient temperature extracted with ether (3×500 mL) The combined organic layers were washed with water, saturated NH4Cl and brine The organic layer was dried over sodium sulfate concentrated in vacuo

Conditions: temp:50.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: A flask was charged with powdered potassium hydroxide (21.89 g, 390.2 mmol), benzoic acid (47.65 g, 390.2 mmol), and DMF (500 mL). The mixture was heated at 50° C. for 1 hour. 3-Chloropentane-2,4-dione (52.5 g, 390.2 mmol) was added and the reaction was stirred 50° C. overnight. The reaction was cooled to ambient temperature, diluted in water (1.5 L) and extracted with ether (3×500 mL). The combined organic layers were washed with water, saturated NH4Cl and brine. The organic layer was dried over sodium sulfate and concentrated in vacuo to afford 2,4-dioxopentan-3-yl benzoate (82.59 g, 96.12% yield) as yellow oil. The reaction was cooled to ambient temperature extracted with ether (3×500 mL) The combined organic layers were washed with water, saturated NH4Cl and brine The organic layer was dried over sodium sulfate concentrated in vacuo

Conditions: temp:50.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: A flask was charged with powdered potassium hydroxide (21.89 g, 390.2 mmol), benzoic acid (47.65 g, 390.2 mmol), and DMF (500 mL) was added. The mixture was heated at 50° C. for 1 hour. 3-Chloropentane-2,4-dione (52.5 g, 390.2 mmol) was added and the reaction was stirred at 50° C. overnight. The reaction was cooled to ambient temperature, diluted in water (1.5 L) and extracted with ether (3×500 mL). The combined organic layers were washed with water, saturated NH4Cl and brine. The organic layer was dried over sodium sulfate and concentrated in vacuo to afford 2,4-dioxopentan-3-yl benzoate (82.59 g, 96.12% yield) as a yellow oil. was added The reaction was cooled to ambient temperature extracted with ether (3×500 mL) The combined organic layers were washed with water, saturated NH4Cl and brine The organic layer was dried over sodium sulfate concentrated in vacuo

Conditions: temp:-78.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: Diisopropylamine (48.6 g, 480 mmol) is dissolved in 350 ml of tetrahydrofuran. At -40° C. there are added dropwise thereto 275 ml (440 mmol) of 1.6 molar butyl-lithium solution in hexane. The mixture is then cooled to -78° C. and 44.02 g (200 mmol) of 3-benzoyloxy-2,4-pentane-dione in 50 ml of tetrahydrofuran are added dropwise thereto within 30 minutes. Subsequently, 22.20 g (300 mmol) of ethyl formate are added dropwise thereto at -78° C. within 30 minutes and the mixture is stirred for 2 hours. The reaction mixture is poured into 600 ml of 1N hydrochloric acid, saturated with sodium chloride and extracted three times with 500 ml of ethyl acetate each time. The combined organic phases are dried over magnesium sulphate, concentrated on a rotary evaporator and give 54.30 g of 4-benzoyloxy-1-hydroxy-1-hexene-3,5-dione. At -40° C. there are added dropwise at -78° C. within 30 minutes extracted three times with 500 ml of ethyl acetate each time The combined organic phases are dried over magnesium sulphate concentrated on a rotary evaporator

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

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

Procedure: Sodium benzoate (106.5 g, 0.74 mol) is suspended in 500 ml of dry DMSO in a three necked flask equipped with a mechanical stirrer and under a gentle stream of argon. Chloroacetylacetone (50 g, 0.37 mol) is then added and the resulting orange mixture is stirred vigorously. After 3 hours the reaction is complete (TLC hexane/ethyl acetate 8/2); the melange is cooled by means of iced water and diluted with 500 ml of water. The solution is then extracted into ether (3×400 ml), washed with water (2×1 L), dried over Na2SO4 and concentrated to dryness in vacuo. The resulting viscous orange oil is pure enough for the next step. The yield is 81.4 g (100%). equipped with a mechanical stirrer and under a gentle stream of argon The solution is then extracted into ether (3×400 ml) washed with water (2×1 L) dried over Na2SO4 concentrated to dryness in vacuo

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

Procedure: Sodium benzoate (106.5 g, 0.74 mol) is suspended in 500 ml of dry DMSO in a three necked flask equipped with a mechanical stirrer and under a gentle stream of argon. Chloroacetylacetone (50 g, 0.37 mol) is then added and the resulting orange mixture is stirred vigorously. After 3 hours the reaction is complete (TLC hexane/ethyl acetate 8/2); the melange is cooled by means of iced water and diluted with 500 ml of water. The solution is then extracted into ether (3×400 ml), washed with water (2×1 L), dried over Na2SO4 and concentrated to dryness in vacuo. The resulting viscous orange oil is pure enough for the next step. The yield is 81.4 g (100%). equipped with a mechanical stirrer and under a gentle stream of argon The solution is then extracted into ether (3×400 ml) washed with water (2×1 L) dried over Na2SO4 concentrated to dryness in vacuo