Ethanol → 11-ethoxyundecanoic acid

HRID 619757Notes

Reaction equation

HRID 619757 reaction equation
Br[CH2:2][CH2:3][CH2:4][CH2:5][CH2:6][CH2:7][CH2:8][CH2:9][CH2:10][CH2:11][C:12]([OH:14])=[O:13].[OH-].[K+].[CH2:17]([OH:19])[CH3:18]>C(OCC)(=O)C>[CH2:17]([O:19][CH2:2][CH2:3][CH2:4][CH2:5][CH2:6][CH2:7][CH2:8][CH2:9][CH2:10][CH2:11][C:12]([OH:14])=[O:13])[CH3:18]

Participants

5

Procedure

11-bromoundecanoic acid (2.25 g, 8.47 mmol) was added to a solution of potassium hydroxide (2.15 g, 38.3 mmol) in absolute ethanol (20 mL) and refluxed for 7 hrs. After cooling and acidification with HCl, solvent was removed under reduced pressure to give a white solid. The sample was dissolved in ethyl acetate and extracted with water. The organic phase was dried over sodium sulfate, and the solvent was removed under reduced pressure. The product was purified by silica column chromatography in 1% diethyl ether/0.3% formic acid/methylene chloride. Solvent was removed under reduced pressure to yield 11-(ethoxy)undecanoic acid (680 mg, 35%): mp 44-45.5° C.; 1H NMR (300 MHz, CDCl3) δ1.20 (t, 3H, J=7.0, CH3), 1.24-1.40 (bm, 12H, methylene envelope), 1.52-1.68 (bm, 4H, O--CH2 --CH2 ; CH2 --CH2 --COOH), 2.34 (t, 2H, J=7.5, CH2 --COOH), 3.41 (t, 2H, J=6.8, --CH2 --CH2), 3.48 (q, 2H, J=7.0, 0--CH2 --CH3), 10.25 (br, 1H, COOH); 13C NMR (75.4 MHz, CDCL3) δ15.27, 24.75, 26.23, 29.11, 29.26, 29.40, 29.55*, 29.80, 34.12, 66.06, 70.76, 179.71; m/z 231 (M+H+).

Workup

  1. temperaturerefluxed for 7 hrs
  2. temperatureAfter cooling
  3. customacidification with HCl, solvent was removed under reduced pressure
  4. customto give a white solid
  5. extractionextracted with water
  6. dry with materialThe organic phase was dried over sodium sulfate
  7. customthe solvent was removed under reduced pressure
  8. customThe product was purified by silica column chromatography in 1% diethyl ether/0.3% formic acid/methylene chloride
  9. customSolvent was removed under reduced pressure

Sources & evidence

ORD record
ord-7b1b910fdae842dcb391056ec7d78f7f
Source dataset
uspto-grants-1999_09
Patent number
US05959145

Reaction notes

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