diethyl 2-hexylpropanedioate

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 diethyl 2-hexylmalonate of Example 8 (244.36 g, 1.000 mol) in 25 mL of absolute ethanol in a 2-L, 3-necked Morton flask was added a solution of potassium hydroxide (59.9 g, 0.907 mol)(weight adjusted for 85% assay of commercial potassium hydroxide) in 450 mL of absolute ethanol dropwise via a 500-mL pressure-equalizing dropping funnel over 75 min. The funnel was washed with 25 mL of absolute ethanol. The reaction mixture was stirred for 2 h, and 300 mL of ethanol was then removed under reduced pressure. Water (500 mL) was added, and the mixture extracted with 500 mL of heptane to remove unreacted diethyl 2-hexylmalonate. The aqueous solution was acidified with 12 M HCl to pH 2 then extracted with 500 mL of heptane. The heptane solution was dried (MgSO4) and the solvent removed under reduced pressure to give 2-(ethoxycarbonyl)octanoic acid as a colorless oil. Traces of ethanol were removed by adding 20 mL of toluene to the crude product, followed by stripping of the solvent at 1 mm Hg of pressure with stirring. The yield was 190.9 g (0.8827 mol, 88.3% based on diethyl 2-hexylmalonate, 97% based on potassium hydroxide). over 75 min The funnel was washed with 25 mL of absolute ethanol 300 mL of ethanol was then removed under reduced pressure Water (500 mL) was added the mixture extracted with 500 mL of heptane to remove unreacted diethyl 2-hexylmalonate then extracted with 500 mL of heptane The heptane solution was dried (MgSO4) the solvent removed under reduced pressure