ethyl 4-methyl-3-oxopentanoate

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:

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 solution of sodium nitrite (43.8 g.) in water (92 ml.) was added dropwise, with stirring, to a solution of ethyl isobutyrylacetate (100.3 g.) in acetic acid (80 ml.) at 0°. After stirring at 0° for 30 minutes at room temperature for 3 hours, water (100 ml.) was added and the mixture extracted with ether. The extracts were washed with water, saturated sodium bicarbonate solution and water. After drying (CaSO4), the solution was evaporated to give ethyl 2-oximino-4-methyl-3-oxopentanoate (112 g.) as a crude oil. the mixture extracted with ether The extracts were washed with water, saturated sodium bicarbonate solution and water After drying (CaSO4) the solution was evaporated

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

Procedure: To a solution of 30.0 grams of ethyl isobutyrylacetate in 130 ml of ethanol (anhydrous,5% methanol) at 10 C. was added dropwise over 30 minutes a solution of 8.7 grams of methyl hydrazine in 30 mls of ethanol. The reaction temperature did not exceed 20 C. After twenty minutes of additional stirring the cooling bath was removed and 2 ml of glacial acetic acid was added. After one hour of stirring at room temperature the reaction was then refluxed for four hours. After stirring overnight at room temperature the reaction was concentrated to yield a yellowish solid. This solid was stirred with 100 ml of hexanes for 30 minutes and the off-white solid was collected and rinsed with 75 ml of hexanes. The solid was dried in a vacuum oven at 45 C. overnight to yield 23.3 g of the desired product, mp 120-122 C. was removed 2 ml of glacial acetic acid was added After one hour of stirring at room temperature the reaction was then refluxed for four hours After stirring overnight at room temperature the reaction was concentrated to yield a yellowish solid the off-white solid was collected rinsed with 75 ml of hexanes The solid was dried in a vacuum oven at 45 C

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

Procedure: Prepared from 2-iodobenzaldehyde, ethyl isobutyrylacetate and concentrated ammonium hydroxide by the procedures described in Example 125, Steps A-B. 1H NMR (300 MHz, CDCl3): δ 0.94 (t, J=7.0 Hz, 6 H), 1.30 (d, J=6.6 Hz, 6 H), 1.34 (d, J=6.6 Hz, 6 H), 3.19 (septet, J=6.6 Hz, 2 H), 4.0 (q, J=7.0 Hz, 4 H), 7.0-7.40 (m, 3 H), 7.85 (m, 1 H).

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

Procedure: Prepared from 4-phenylbenzaldehyde, ethyl isobutyrylacetate and concentrated ammonium hydroxide by the procedures described in Example 125, Steps A-E. 1H NMR (300 MHz, CDCl3): δ 0.73 (t, J=7.4 Hz, 3 H), 0.93 (t, J=7.0 Hz, 3 H), 1.10-1.40 (m, 14 H), 1.97 (tdd, J=7.0, 7.0, 1.1 Hz, 2 H), 3.10 (m, 1 H), 3.45 (m, 1 H), 4.0 (q, J=7.4 Hz, 2 H), 5.40 (m, 1 H), 6.10 (dt, J=16.2, 1.1 Hz, 1 H), 7.20-7.70 (m, 9 H). mp 104-106° C.