ethyl 2,4-dimethyl-3-oxopentanoate

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

Procedure: To anhydrous ethanol (110 mL) was added sodium metal (1.16 g, 50.4 mmol) and the mixture was stirred until dissolution was complete. To this solution was added thiourea (1.79 g, 23.5 mmol) and ethyl 2,4-dimethyl-3-oxopentanoate (2.89 g, 16.8 mmol). The reaction mixture was stirred at 85° C. for 20 h then cooled and concentrated. The residue was diluted with water, the pH adjusted to 4 with 1 N hydrochloric acid then extracted with ethyl acetate (3×80 mL). The combined organic layers were washed with brine, dried over anhydrous sodium sulfate, filtered and concentrated to provide 6-isopropyl-5-methyl-2-thioxo-2,3-dihydropyrimidin-4(1H)-one (2.40 g, 78% yield) as a tan solid that was used without further purification. C8H12N2OS: 185 (MH+). The reaction mixture was stirred at 85° C. for 20 h then cooled concentrated The residue was diluted with water then extracted with ethyl acetate (3×80 mL) The combined organic layers were washed with brine dried over anhydrous sodium sulfate filtered concentrated

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

Procedure: To anhydrous ethanol (110 mL) was added sodium metal (1.16 g, 50.4 mmol) and the mixture was stirred until dissolution was complete. To this solution was added thiourea (1.79 g, 23.5 mmol) and ethyl 2,4-dimethyl-3-oxopentanoate (2.89 g, 16.8 mmol). The reaction mixture was stirred at 85° C. for 20 h then cooled and concentrated. The residue was diluted with water, the pH adjusted to 4 with 1 N hydrochloric acid then extracted with ethyl acetate (3×80 mL). The combined organic layers were washed with brine, dried over anhydrous sodium sulfate, filtered and concentrated to provide 6-isopropyl-5-methyl-2-thioxo-2,3-dihydropyrimidin-4(1H)-one (2.40 g, 78% yield) as a tan solid that was used without further purification. C8H12N2OS: 185 (MH+). The reaction mixture was stirred at 85° C. for 20 h then cooled concentrated The residue was diluted with water then extracted with ethyl acetate (3×80 mL) The combined organic layers were washed with brine dried over anhydrous sodium sulfate filtered concentrated

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

Procedure: A solution of ethyl 4-methyl-3-oxopentanoate (3.0 g, 19.0 mmol) and potassium carbonate (7.86 g, 56.9 mmol) in THF (40 mL) was stirred at room temperature for 3 h under N2 (g). The mixture was cooled to 0° C. and methyl iodide (3.23 g, 22.8 mmol) was added dropwise over 5 min. The reaction mixture was allowed to warm to room temperature and stirred for 16 h. Subsequent filtration and concentration provided ethyl 2,4-dimethyl-3-oxopentanoate (2.89 g, 89% yield) as a clear yellow oil that was used without further purification. MS (EI) for C9H16O3: 172 (MH+). to warm to room temperature Subsequent filtration and concentration

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

Procedure: A solution of ethyl 4-methyl-3-oxopentanoate (3.0 g, 19.0 mmol) and potassium carbonate (7.86 g, 56.9 mmol) in THF (40 mL) was stirred at room temperature for 3 h under N2 (g). The mixture was cooled to 0° C. and methyl iodide (3.23 g, 22.8 mmol) was added dropwise over 5 min. The reaction mixture was allowed to warm to room temperature and stirred for 16 h. Subsequent filtration and concentration provided ethyl 2,4-dimethyl-3-oxopentanoate (2.89 g, 89% yield) as a clear yellow oil that was used without further purification. MS (EI) for C9H16O3: 172 (MH+). to warm to room temperature Subsequent filtration and concentration

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

Procedure: To anhydrous ethanol (110 mL) was added sodium metal (1.16 g, 50.4 mmol) and the mixture was stirred until dissolution was complete. To this solution was added thiourea (1.79 g, 23.5 mmol) and ethyl 2,4-dimethyl-3-oxopentanoate (2.89 g, 16.8 mmol). The reaction mixture was stirred at 85° C. for 20 h then cooled and concentrated. The residue was diluted with water, the pH adjusted to 4 with 1 N hydrochloric acid then extracted with ethyl acetate (3×80 mL). The combined organic layers were washed with brine, dried over anhydrous sodium sulfate, filtered and concentrated to provide 6-isopropyl-5-methyl-2-thioxo-2,3-dihydropyrimidin-4(1H)-one (2.40 g, 78% yield) as a tan solid that was used without further purification. C8H12N2OS: 185 (MH+). The reaction mixture was stirred at 85° C. for 20 h then cooled concentrated The residue was diluted with water then extracted with ethyl acetate (3×80 mL) The combined organic layers were washed with brine dried over anhydrous sodium sulfate filtered concentrated

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

Procedure: A solution of ethyl 4-methyl-3-oxopentanoate (3.0 g, 19.0 mmol) and potassium carbonate (7.86 g, 56.9 mmol) in THF (40 mL) was stirred at room temperature for 3 h under N2 (g). The mixture was cooled to 0° C. and methyl iodide (3.23 g, 22.8 mmol) was added dropwise over 5 min. The reaction mixture was allowed to warm to room temperature and stirred for 16 h. Subsequent filtration and concentration provided ethyl 2,4-dimethyl-3-oxopentanoate (2.89 g, 89% yield) as a clear yellow oil that was used without further purification. MS (EI) for C9H16O3: 172 (MH+). to warm to room temperature Subsequent filtration and concentration

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

Procedure: To anhydrous ethanol (110 mL) was added sodium metal (1.16 g, 50.4 mmol) and the mixture was stirred until dissolution was complete. To this solution was added thiourea (1.79 g, 23.5 mmol) and ethyl 2,4-dimethyl-3-oxopentanoate (2.89 g, 16.8 mmol). The reaction mixture was stirred at 85° C. for 20 h then cooled and concentrated. The residue was diluted with water, the pH adjusted to 4 with 1 N hydrochloric acid then extracted with ethyl acetate (3×80 mL). The combined organic layers were washed with brine, dried over anhydrous sodium sulfate, filtered and concentrated to provide 6-isopropyl-5-methyl-2-thioxo-2,3-dihydropyrimidin-4(1H)-one (2.40 g, 78% yield) as a tan solid that was used without further purification. C8H12N2OS: 185 (MH+). The reaction mixture was stirred at 85° C. for 20 h then cooled concentrated The residue was diluted with water then extracted with ethyl acetate (3×80 mL) The combined organic layers were washed with brine dried over anhydrous sodium sulfate filtered concentrated

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

Procedure: A solution of ethyl 4-methyl-3-oxopentanoate (3.0 g, 19.0 mmol) and potassium carbonate (7.86 g, 56.9 mmol) in THF (40 mL) was stirred at room temperature for 3 h under N2 (g). The mixture was cooled to 0° C. and methyl iodide (3.23 g, 22.8 mmol) was added dropwise over 5 min. The reaction mixture was allowed to warm to room temperature and stirred for 16 h. Subsequent filtration and concentration provided ethyl 2,4-dimethyl-3-oxopentanoate (2.89 g, 89% yield) as a clear yellow oil that was used without further purification. MS (EI) for C9H16O3: 172 (MH+). to warm to room temperature Subsequent filtration and concentration