ethyl 2,4-dioxoheptanoate

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 refluxing solution of sodium ethoxide (51.2 g, 0.75 mmol) in ethanol (170 ml) was added dropwise over 30 minutes a solution of 2-pentanone (59 g, 0.68 mol) in diethyl oxalate (99 g, 0.68 mol). The resulting turbid yellow mixture was refluxed further for 2 hours, cooled to room temperature, poured over 500 g ice with stirring and adjusted to pH 1-2 with concentrated sulfuric acid (~40 ml). The organic phase was extracted with benzene (3×300 ml), washed once with saturated aqueous sodium chloride and dried over anhydrous sodium sulfate, before being filtered, concentrated, and fractionally distilled at 0.1 mm Hg to give 48.2 g (38%) of the title compound as a yellow liquid; b.p. 85°-95° C. The resulting turbid yellow mixture was refluxed further for 2 hours The organic phase was extracted with benzene (3×300 ml) washed once with saturated aqueous sodium chloride dried over anhydrous sodium sulfate before being filtered concentrated fractionally distilled at 0.1 mm Hg

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

Procedure: To refluxing solution of sodium ethoxide (51.2 g, 0.75 mmol) in ethanol (170 ml) was added dropwise over 30 minutes a solution of 2-pentanone (59 g, 0.68 mol) in diethyl oxalate (99 g, 0.68 mol). The resulting turbid yellow mixture was refluxed further for 2 hours, cooled to room temperature, poured over 500 g ice with stirring and adjusted to pH 1-2 with concentrated sulfuric acid (~40 ml). The organic phase was extracted with benzene (3×300 ml), washed once with saturated aqueous sodium chloride and dried over anhydrous sodium sulfate, before being filtered, concentrated, and fractionally distilled at 0.1 mm Hg to give 48.2 g (38%) of the title compound as a yellow liquid; b.p. 85-95° C. The resulting turbid yellow mixture was refluxed further for 2 hours The organic phase was extracted with benzene (3×300 ml) washed once with saturated aqueous sodium chloride dried over anhydrous sodium sulfate before being filtered concentrated fractionally distilled at 0.1 mm Hg

Conditions: temp:62.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: To a solution of ethyl 2,4-dioxoheptanoate (446 mg, 2.397 mmol) in benzene (5 mL) was added 1-(1-methylethyl)-1H-pyrazol-5-amine (300 mg, 2.397 mmol), and the mixture was stirred at 62° C. for 18 h. The reaction mixture was concentrated in vacuo and the residue purified by column chromatography (Silica gel, gradient of 0 to 100% EtOAc/hexanes) to give 370 mg (56%) of product. LCMS E-S (M+H)=276.1. 1H NMR (400 MHz, CHLOROFORM-d) δ ppm 0.99-1.12 (m, 3H), 1.46-1.54 (m, 3H), 1.58-1.70 (m, 6H), 1.82-1.96 (m, 2H), 2.91-3.02 (m, 2H), 4.51 (q, J=7.2 Hz, 2H), 5.28-5.44 (m, 1H), 7.58-7.68 (s, 1H), 8.27-8.40 (s, 1H) The reaction mixture was concentrated in vacuo the residue purified by column chromatography (Silica gel, gradient of 0 to 100% EtOAc/hexanes)

Conditions: temp:62.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: To a solution of ethyl 2,4-dioxoheptanoate (446 mg, 2.397 mmol) in benzene (5 mL) was added 1-(1-methylethyl)-1H-pyrazol-5-amine (300 mg, 2.397 mmol), and the mixture was stirred at 62° C. for 18 h. The reaction mixture was concentrated in vacuo and the residue purified by column chromatography (Silica gel, gradient of 0 to 100% EtOAc/hexanes) to give 370 mg (56%) of product. LCMS E-S (M+H)=276.1. 1H NMR (400 MHz, CHLOROFORM-d) δ ppm 0.99-1.12 (m, 3H), 1.46-1.54 (m, 3H), 1.58-1.70 (m, 6H), 1.82-1.96 (m, 2H), 2.91-3.02 (m, 2H), 4.51 (q, J=7.2 Hz, 2H), 5.28-5.44 (m, 1H), 7.58-7.68 (s, 1H), 8.27-8.40 (s, 1H) The reaction mixture was concentrated in vacuo the residue purified by column chromatography (Silica gel, gradient of 0 to 100% EtOAc/hexanes)

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

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

Procedure: To refluxing solution of sodium ethoxide (51.2 g, 0.75 mmol) in ethanol (170 ml) was added dropwise over 30 minutes a solution of 2-pentanone (59 g, 0.68 mol) in diethyl oxalate (99 g, 0.68 mol). The resulting turbid yellow mixture was refluxed further for 2 hours, cooled to room temperature, poured over 500 g ice with stirring and adjusted to pH 1-2 with concentrated sulfuric acid (~40 ml). The organic phase was extracted with benzene (3×300 ml), washed once with saturated aqueous sodium chloride and dried over anhydrous sodium sulfate, before being filtered, concentrated, and fractionally distilled at 0.1 mm Hg to give 48.2 g (38%) of the title compound as a yellow liquid; b.p. 85°-95° C. The resulting turbid yellow mixture was refluxed further for 2 hours The organic phase was extracted with benzene (3×300 ml) washed once with saturated aqueous sodium chloride dried over anhydrous sodium sulfate before being filtered concentrated fractionally distilled at 0.1 mm Hg

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

Procedure: To refluxing solution of sodium ethoxide (51.2 g, 0.75 mmol) in ethanol (170 ml) was added dropwise over 30 minutes a solution of 2-pentanone (59 g, 0.68 mol) in diethyl oxalate (99 g, 0.68 mol). The resulting turbid yellow mixture was refluxed further for 2 hours, cooled to room temperature, poured over 500 g ice with stirring and adjusted to pH 1-2 with concentrated sulfuric acid (~40 ml). The organic phase was extracted with benzene (3×300 ml), washed once with saturated aqueous sodium chloride and dried over anhydrous sodium sulfate, before being filtered, concentrated, and fractionally distilled at 0.1 mm Hg to give 48.2 g (38%) of the title compound as a yellow liquid; b.p. 85°-95° C. The resulting turbid yellow mixture was refluxed further for 2 hours The organic phase was extracted with benzene (3×300 ml) washed once with saturated aqueous sodium chloride dried over anhydrous sodium sulfate before being filtered concentrated fractionally distilled at 0.1 mm Hg

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

Procedure: To refluxing solution of sodium ethoxide (51.2 g, 0.75 mmol) in ethanol (170 ml) was added dropwise over 30 minutes a solution of 2-pentanone (59 g, 0.68 mol) in diethyl oxalate (99 g, 0.68 mol). The resulting turbid yellow mixture was refluxed further for 2 hours, cooled to room temperature, poured over 500 g ice with stirring and adjusted to pH 1-2 with concentrated sulfuric acid (~40 ml). The organic phase was extracted with benzene (3×300 ml), washed once with saturated aqueous sodium chloride and dried over anhydrous sodium sulfate, before being filtered, concentrated, and fractionally distilled at 0.1 mm Hg to give 48.2 g (38%) of the title compound as a yellow liquid; b.p. 85°-95° C. The resulting turbid yellow mixture was refluxed further for 2 hours The organic phase was extracted with benzene (3×300 ml) washed once with saturated aqueous sodium chloride dried over anhydrous sodium sulfate before being filtered concentrated fractionally distilled at 0.1 mm Hg

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

Procedure: To refluxing solution of sodium ethoxide (51.2 g, 0.75 mmol) in ethanol (170 ml) was added dropwise over 30 minutes a solution of 2-pentanone (59 g, 0.68 mol) in diethyl oxalate (99 g, 0.68 mol). The resulting turbid yellow mixture was refluxed further for 2 hours, cooled to room temperature, poured over 500 g ice with stirring and adjusted to pH 1-2 with concentrated sulfuric acid (~40 ml). The organic phase was extracted with benzene (3×300 ml), washed once with saturated aqueous sodium chloride and dried over anhydrous sodium sulfate, before being filtered, concentrated, and fractionally distilled at 0.1 mm Hg to give 48.2 g (38%) of the title compound as a yellow liquid; b.p. 85°-95° C. The resulting turbid yellow mixture was refluxed further for 2 hours The organic phase was extracted with benzene (3×300 ml) washed once with saturated aqueous sodium chloride dried over anhydrous sodium sulfate before being filtered concentrated fractionally distilled at 0.1 mm Hg