ethyl 5,5-dimethyl-2,4-dioxohexanoate

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

Procedure: A solution of 3-bromophenylhydrazine hydrochloride (0.5 g, 2.2 mmol) and ethyl 5,5-dimethyl-2,4-dioxohexanoate (0.54 g, 2.68 mmol) in acetic acid (10 ml) was refluxed for 16 hours. The reaction was cooled to room temperature, and the solvent was removed under reduced pressure. The residue was partitioned between ethyl acetate and water. The organic layer was washed with water, saturated bicarbonate and brine, and dried over sodium sulfate, filtered and concentrated. The crude material was purified by column chromatography (4.8:0.2 hexanes/ethyl acetate) to give ethyl 1-(3-bromophenyl)-5-tert-butyl-1H-pyrazole-3-carboxylate (0.59 g, 74%) as a syrup. the solvent was removed under reduced pressure The residue was partitioned between ethyl acetate and water The organic layer was washed with water, saturated bicarbonate and brine dried over sodium sulfate filtered concentrated The crude material was purified by column chromatography (4.8:0.2 hexanes/ethyl acetate)

Conditions: temp:80.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: 146 g (1 mol) of oxalic acid diethyl ester are added dropwise to 367.2 g of a 20% strength sodium ethylate solution in ethanol at 5° C. in the course of one hour, whilst stirring. 100 g of technical grade pinacolin are allowed to run in and the mixture is stirred for a further 15 minutes. It is then heated to 80° C. and heated under reflux for 3 hours. The solution is subsequently evaporated to dryness in a rotary evaporator. The residue is suspended in 200 ml of toluene and the suspension is stirred with 253 g of aqueous sulphuric acid (20.9% strength by weight) at 50° C. for 1 hour. The organic phase is separated off and distilled. 177 g of pivaloylpyruvic acid ethyl ester (88.2% of the theoretical yield) are obtained with a purity of 99.6% (by analysis by gas chromatography). is stirred for a further 15 minutes heated under reflux for 3 hours The solution is subsequently evaporated to dryness in a rotary evaporator the suspension is stirred with 253 g of aqueous sulphuric acid (20.9% strength by weight) at 50° C. for 1 hour The organic phase is separated off distilled

Conditions: temp:80.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: 146 g (1 mol) of oxalic acid diethyl ester are added dropwise to 367.2 g of a 20% strength sodium ethylate solution in ethanol at 5° C. in the course of one hour, whilst stirring. 100 g of technical grade pinacolin are allowed to run in and the mixture is stirred for a further 15 minutes. It is then heated to 80° C. and heated under reflux for 3 hours. The solution is subsequently evaporated to dryness in a rotary evaporator. The residue is suspended in 200 ml of toluene and the suspension is stirred with 253 g of aqueous sulphuric acid (20.9% strength by weight) at 50° C. for 1 hour. The organic phase is separated off and distilled. 177 g of pivaloylpyruvic acid ethyl ester (88.2% of the theoretical yield) are obtained with a purity of 99.6% (by analysis by gas chromatography). is stirred for a further 15 minutes heated under reflux for 3 hours The solution is subsequently evaporated to dryness in a rotary evaporator the suspension is stirred with 253 g of aqueous sulphuric acid (20.9% strength by weight) at 50° C. for 1 hour The organic phase is separated off distilled

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

Procedure: [Bis(trifluoroacetoxy)iodo]benzene (430 mg, 1.00 mmol) was dissolved in anhydrous MeOH (4 mL), the resulting solution was stirred at room temperature for 3 min. BF3.OEt2 (0.123 mL, 1.00 mmol) was then added via syringe. Ethyl trimethylacetopyruvate (200 mg, 1.00 mmol) was added dropwise via syringe and the resulting mixture was stirred at room temperature for 12 h. The solvent was removed under reduced pressure and the resulting residue was dissolved in dry EtOH (2 mL). CH3NHNH2 (52.6 μL, 1.00 mmol) was added via syringe and the resulting mixture was stirred at 80° C. for 8 h. The solvent was removed under reduced pressure and the resulting residue was chromatographed on a 24-g SiO2 pre-packed column eluting with 0:1-3:7 EtOAc/hexanes to yield 5-tert-butyl-4-methoxy-2-methyl-2H-pyrazole-3-carboxylic acid ethyl ester. 1H-NMR (400 MHz, CDCl3) δ: 4.39 (q, J=7.1 Hz, 2H), 4.03 (s, 3H), 3.83 (s, 3H), 1.42 (t, J=7.2 Hz, 3H), 1.34 (s, 9H). the resulting mixture was stirred at room temperature for 12 h The solvent was removed under reduced pressure the resulting residue was dissolved in dry EtOH (2 mL) the resulting mixture was stirred at 80° C. for 8 h The solvent was removed under reduced pressure the resulting residue was chromatographed on a 24-g SiO2 pre-packed column eluting with 0:1-3:7 EtOAc/hexanes

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

Procedure: Ethyl 5,5-dimethyl-2,4-dioxo-hexanoate (1.02 g, 5.09 mmol) was dissolved in absolute EtOH (20 mL). CH3NHNH2 (0.270 mL, 5.09 mmol) was added dropwise and the resulting mixture was stirred at room temperature for 2 h. The resulting mixture was warmed to 80° C. for 4 h, and then cooled to room temperature. The solvent was removed under reduced pressure, and the resulting residue was chromatographed using a 70-g pre-packed SiO2 column eluting with 1:19 EtOAc-hexanes to yield the title compound as a colorless oil. 1H-NMR (400 MHz, CDCl3) δ: 6.68 (s, 1H), 4.33 (q, J=7.2 Hz, 2H), 4.12 (s, 3H), 1.38 (t, J=7.1 Hz, 3H), 1.30 (s, 9H). The resulting mixture was warmed to 80° C. for 4 h cooled to room temperature The solvent was removed under reduced pressure the resulting residue was chromatographed eluting with 1:19 EtOAc-hexanes

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

Procedure: The title compound was prepared in the same manner as described for intermediate 61 using ethyl 5,5-dimethyl-2,4-dioxohexanoate (392 mg, 1.958 mmol), benzene (10 mL), 1-(1,1-dimethylethyl)-3-methyl-1H-pyrazol-5-amine (300 mg, 1.958 mmol), and acetic acid (2 mL). The crude product was purified by column chromatography (Silica gel, eluent: 0 to 100% EtOAc/hexanes) to give 530 mg (85%) of product. LCMS E-S (M+H)=318.3. 1H NMR (400 MHz, CHLOROFORM-d) δ ppm 1.43-1.52 (m, 12H), 1.84 (s, 9H), 2.67 (s, 3H), 4.50 (q, J=7.07 Hz, 2H), 7.59 (s, 1H). The crude product was purified by column chromatography (Silica gel, eluent: 0 to 100% EtOAc/hexanes)

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

Procedure: A mixture of ethyl trimethylacetopyruvate (0.40 g, 2 mmol), 4-thiophene-3-ylaniline (0.35 g, 2 mmol), 2-(methoxycarbonylmethyloxy)benzaldehyde (0.39, 2 mmol), acetic acid (0.057 mL, 1 mmol) and dioxane (4 mL) was heated at reflux overnight. After the reaction was completed, saturated sodium bicarbonate solution and brine were poured into the reaction mixture, and the resulting mixture was extracted with ethyl acetate. The extract was dried over anhydrous sodium sulphate, and then concentrated in vacuo. The resulting residue was purified on a silica gel column chromatography (methanol/chloroform), and the aimed compound was triturated with ethyl acetate and diisopropyl ether to give 4-(2,2-dimethylpropionyl)-3-hydroxy-5-(2-methoxycarbonylmethyloxyphenyl)-1-(4-thiophene-3-ylphenyl)-1,5-dihydropyrrole-2-one (0.42 g, yield: 41%) as pale brown solid. was heated at reflux overnight the resulting mixture was extracted with ethyl acetate The extract was dried over anhydrous sodium sulphate concentrated in vacuo The resulting residue was purified on a silica gel column chromatography (methanol/chloroform) the aimed compound was triturated with ethyl acetate and diisopropyl ether

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

Procedure: The title compound was prepared in the same manner as described for intermediate 61 using ethyl 5,5-dimethyl-2,4-dioxohexanoate (392 mg, 1.958 mmol), benzene (10 mL), 1-(1,1-dimethylethyl)-3-methyl-1H-pyrazol-5-amine (300 mg, 1.958 mmol), and acetic acid (2 mL). The crude product was purified by column chromatography (Silica gel, eluent: 0 to 100% EtOAc/hexanes) to give 530 mg (85%) of product. LCMS E-S (M+H)=318.3. 1H NMR (400 MHz, CHLOROFORM-d) δ ppm 1.43-1.52 (m, 12 H), 1.84 (s, 9 H), 2.67 (s, 3 H), 4.50 (q, J=7.07 Hz, 2 H), 7.59 (s, 1 H). The crude product was purified by column chromatography (Silica gel, eluent: 0 to 100% EtOAc/hexanes)

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

Procedure: [Bis(trifluoroacetoxy)iodo]benzene (430 mg, 1.00 mmol) was dissolved in anhydrous MeOH (4 mL), the resulting solution was stirred at room temperature for 3 min. BF3.OEt2 (0.123 mL, 1.00 mmol) was then added via syringe. Ethyl trimethylacetopyruvate (200 mg, 1.00 mmol) was added dropwise via syringe and the resulting mixture was stirred at room temperature for 12 h. The solvent was removed under reduced pressure and the resulting residue was dissolved in dry EtOH (2 mL). CH3NHNH2 (52.6 μL, 1.00 mmol) was added via syringe and the resulting mixture was stirred at 80° C. for 8 h. The solvent was removed under reduced pressure and the resulting residue was chromatographed on a 24-g SiO2 pre-packed column eluting with 0:1-3:7 EtOAc/hexanes to yield 5-tert-butyl-4-methoxy-2-methyl-2H-pyrazole-3-carboxylic acid ethyl ester. 1H-NMR (400 MHz, CDCl3) δ: 4.39 (q, J=7.1 Hz, 2H), 4.03 (s, 3H), 3.83 (s, 3H), 1.42 (t, J=7.2 Hz, 3H), 1.34 (s, 9H). the resulting mixture was stirred at room temperature for 12 h The solvent was removed under reduced pressure the resulting residue was dissolved in dry EtOH (2 mL) the resulting mixture was stirred at 80° C. for 8 h The solvent was removed under reduced pressure the resulting residue was chromatographed on a 24-g SiO2 pre-packed column eluting with 0:1-3:7 EtOAc/hexanes

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

Procedure: Ethyl 5,5-dimethyl-2,4-dioxo-hexanoate (1.02 g, 5.09 mmol) was dissolved in absolute EtOH (20 mL). CH3NHNH2 (0.270 mL, 5.09 mmol) was added dropwise and the resulting mixture was stirred at room temperature for 2 h. The resulting mixture was warmed to 80° C. for 4 h, and then cooled to room temperature. The solvent was removed under reduced pressure, and the resulting residue was chromatographed using a 70-g pre-packed SiO2 column eluting with 1:19 EtOAc-hexanes to yield the title compound as a colorless oil. 1H-NMR (400 MHz, CDCl3) δ: 6.68 (s, 1H), 4.33 (q, J=7.2 Hz, 2H), 4.12 (s, 3H), 1.38 (t, J=7.1 Hz, 3H), 1.30 (s, 9H). The resulting mixture was warmed to 80° C. for 4 h cooled to room temperature The solvent was removed under reduced pressure the resulting residue was chromatographed eluting with 1:19 EtOAc-hexanes

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

Procedure: [Bis(trifluoroacetoxy)iodo]benzene (430 mg, 1.00 mmol) was dissolved in anhydrous MeOH (4 mL), the resulting solution was stirred at room temperature for 3 min. BF3.OEt2 (0.123 mL, 1.00 mmol) was then added via syringe. Ethyl trimethylacetopyruvate (200 mg, 1.00 mmol) was added dropwise via syringe and the resulting mixture was stirred at room temperature for 12 h. The solvent was removed under reduced pressure and the resulting residue was dissolved in dry EtOH (2 mL). CH3NHNH2 (52.6 μL, 1.00 mmol) was added via syringe and the resulting mixture was stirred at 80° C. for 8 h. The solvent was removed under reduced pressure and the resulting residue was chromatographed on a 24-g SiO2 pre-packed column eluting with 0:1-3:7 EtOAc/hexanes to yield 5-tert-butyl-4-methoxy-2-methyl-2H-pyrazole-3-carboxylic acid ethyl ester. 1H-NMR (400 MHz, CDCl3) δ: 4.39 (q, J=7.1 Hz, 2H), 4.03 (s, 3H), 3.83 (s, 3H), 1.42 (t, J=7.2 Hz, 3H), 1.34 (s, 9H). the resulting mixture was stirred at room temperature for 12 h The solvent was removed under reduced pressure the resulting residue was dissolved in dry EtOH (2 mL) the resulting mixture was stirred at 80° C. for 8 h The solvent was removed under reduced pressure the resulting residue was chromatographed on a 24-g SiO2 pre-packed column eluting with 0:1-3:7 EtOAc/hexanes

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

Procedure: Ethyl 5,5-dimethyl-2,4-dioxo-hexanoate (1.02 g, 5.09 mmol) was dissolved in absolute EtOH (20 mL). CH3NHNH2 (0.270 mL, 5.09 mmol) was added dropwise and the resulting mixture was stirred at room temperature for 2 h. The resulting mixture was warmed to 80° C. for 4 h, and then cooled to room temperature. The solvent was removed under reduced pressure, and the resulting residue was chromatographed using a 70-g pre-packed SiO2 column eluting with 1:19 EtOAc-hexanes to yield the title compound as a colorless oil. 1H-NMR (400 MHz, CDCl3) δ: 6.68 (s, 1H), 4.33 (q, J=7.2 Hz, 2H), 4.12 (s, 3H), 1.38 (t, J=7.1 Hz, 3H), 1.30 (s, 9H). The resulting mixture was warmed to 80° C. for 4 h cooled to room temperature The solvent was removed under reduced pressure the resulting residue was chromatographed eluting with 1:19 EtOAc-hexanes