ethyl 3-oxoheptanoate

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 a solution of 3.77 g (43.8 mmol) ethyl 3-oxoheptanoate in 200 mL DMSO was added 1.75 g (43.8 mmol) 65% NaH in oil. After 10 minutes, 6.5 g (21.9 mmol) α-bromo-4-iodotoluene was added. The mixture was allowed to stir for 2 hours. It was then poured into an ice/brine mixture and extracted 3 times with ether. The combined organic material was washed with brine, dried over MgSO4, stripped of solvent in vacuo, then Still flash chromatographed in 40% CH2Cl2 /hexane to give 2.46 g of the title compound, 29% yield. Rf 0.23 in 40% CH2Cl2 /hexane, visualized by UV and ninhydrin stain; extracted 3 times with ether The combined organic material was washed with brine dried over MgSO4 Still flash chromatographed in 40% CH2Cl2 /hexane

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

Procedure: To a solution of dimedone (0.70 g, 5.0 mmole) in hot ethanol (15 ml) was added 5-phenyl-2-thiophenecarboxaldehyde (0.940 g, 5.0 mmole), ethyl propylacetoacetate (0.80 ml, 5.0 mmole) and lastly ammonium acetate (0.770 g, 10.0 mmole). The mixture was held at reflux for 48 h. No precipitate was observed. The ethanol was removed in vacuo to provide a crude viscous material which was subjected to a 100 g SiO2 flash column using 40% ethyl acetate:hexanes as eluent. The desired product (1.54 g, 68%) was obtained as a yellow amorphous solid. Rf=0.37 in 1:1 ethyl acetate hexanes. 1H NMR (400 MHz; CDCl3) d 7.5 (bd, 2H, J=7.0 Hz); 7.32-7.25 (m, 2H); 7.19 (at, 1H, J=7.4 Hz); 7.04 (d, 1H, J=7.4 Hz); 6.8 (d, 1H, J=3.5 Hz); 6.38 (bs, 1H); 5.41 (s, 1H); 4.22-3.90 (m, 2H); 2.90-2.80 (m, 1H); 2.72-2.63 (m, 1H); 2.35 (d, 1H, J=16.8 Hz); 2.25 (d, 1H, J=16.8 Hz); 2.3-2.2 (On, 2H); 1.74-1.62 (m, 2H); 1.25 (at, 3H, J=7.0 Hz); 1.07 (s, 3H); 1.02 (s, 3H); 1.01 (at, 3H, J=7.0 Hz); 1.05-0.95 (m, 2H). LC MS shows MH+ at 450; 2M+H at 899 and 2M+Na at 921. at reflux for 48 h The ethanol was removed in vacuo to provide a crude viscous material which

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

Procedure: The title compound was prepared from 2,1,3-benzoxadiazole-4-aldehyde, 3-aminopyrazole and ethyl 3-ketoheptanoate in the same manner as in Example 1.

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

Procedure: The title compound was prepared from 2,1,3-benzoxadiazole-4-aldehyde, 3-aminopyrazole and ethyl 3-ketoheptanoate in the same manner as in Example 1.

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

Procedure: The title compound was prepared from 2-methoxybenzaldehyde, 3-aminopyrazole and ethyl 3-ketoheptanoate in the same manner as in Example 1.

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

Procedure: The title compound was prepared from 2-methoxybenzaldehyde, 3-aminopyrazole and ethyl 3-ketoheptanoate in the same manner as in Example 1.

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

Procedure: The title compound was prepared from 2-chlorobenzaldehyde, 3-aminopyrazole and ethyl 3-ketoheptanoate in the same manner as in Example 1.

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

Procedure: The title compound was prepared from 2-chlorobenzaldehyde, 3-aminopyrazole and ethyl 3-ketoheptanoate in the same manner as in Example 1.

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

Procedure: To a solution of 3.77 g (43.8 mmol) ethyl 3-oxoheptanoate in 200 mL DMSO was added 1.75 g (43.8 mmol) 65% NaH in oil. After 10 minutes, 6.5 g (21.9 mmol) α-bromo-4-iodotoluene was added. The mixture was allowed to stir for 2 hours. It was then poured into an ice/brine mixture and extracted 3 times with ether. The combined organic material was washed with brine, dried over MgSO4, stripped of solvent in vacuo, then Still flash chromatographed in 40% CH2Cl2 /hexane to give 2.46 g of the title compound, 29% yield. Rf 0.23 in 40% CH2Cl2 /hexane, visualized by UV and ninhydrin stain; extracted 3 times with ether The combined organic material was washed with brine dried over MgSO4 Still flash chromatographed in 40% CH2Cl2 /hexane

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

Procedure: Ethyl 3-ketoheptanoate (2.07 g, 12 mmol) was dissolved in dimethylformamide (60 mL) under argon and sodium hydride (357 mg, 14.4 mmol) was added. After 30 minutes at room temperature the solid N-phenyltrifluoro-methanesulfonamide (Tetra. Letters, (1983), 24, 979) (4.97 g, 13.8 mmol) was added. The reaction was stirred for 2 hours, diluted with ether/water and the usual workup gave after chromatography with 5:95 ether/hexane 3.45 g (94%) of ethyl 3-trifluoromethanesulfonyloxy-2-heptenoate.