Hydrochloric Acid → 1-(2-Ethyl-butyl)-cyclohexanecarboxylic acid isopropyl ester

HRID 656700Notes

Reaction equation

HRID 656700 reaction equation
C1(NC2CCCCC2)CCCCC1.CCCCCC.[CH:20]([O:23][C:24]([CH:26]1[CH2:31][CH2:30][CH2:29][CH2:28][CH2:27]1)=[O:25])([CH3:22])[CH3:21].Br[CH2:33][CH:34]([CH2:37][CH3:38])[CH2:35][CH3:36].Cl>C1COCC1.O>[CH:20]([O:23][C:24]([C:26]1([CH2:33][CH:34]([CH2:37][CH3:38])[CH2:35][CH3:36])[CH2:31][CH2:30][CH2:29][CH2:28][CH2:27]1)=[O:25])([CH3:22])[CH3:21]

Participants

8

Reactant 5

HCID 313Hydrochloric AcidHCID 7582DicyclohexylamineHCID 8058HexaneHCID 77432Pentane, 3-(bromomethyl)-HCID 81039Cyclohexanecarboxylic acid, 1-methylethyl ester

Product 1

HCID 445486591-(2-Ethyl-butyl)-cyclohexanecarboxylic acid isopropyl esterYield 88.1%

Reagents, catalysts & solvents 2

HCID 962WaterSolventHCID 8028TetrahydrofuranSolvent3×

Conditions

Temperature
0 °C

Procedure

To a solution of dicyclohexylamine (4.263 g, 23.5 mmol) in THF (10 mL) 1.6 M n-BuLi in hexane (13.23 mL, 21.15 mmol) was added with stirring over 20 min at temperature between −20° C. and −15° C. This orange suspension was stirred 10 min at −20° C. and then warmed up to 0° C. To this orange suspension a solution of cyclohexanecarboxylic acid isopropyl ester (3.0 g, 17.63 mmol) in THF (22 mL) was added over 15 min at 0° C. The resulting solution was stirred 30 min at 0° C., then 1-bromo-2-ethylbutane (4.073 g, 24.7 mmol) in THF (11 mL) was added at the same temperature over 15 min. Stirring at 0° C. was continued overnight and for an additional 2 h at room temperature. At 5° C. cold water (20 mL) was added, followed by 2N HCl (50 mL). The white suspension was filtered and the filter cake was washed with water and ethyl acetate. The organic phase of the filtrate was washed with sat. aq. NaHCO3 and with aq. NaCl. The aqueous phases were extracted with ethyl acetate. The organic phases were combined, dried over sodium sulfate and concentrated. The crude product (4.7 g) was distilled at 50° C. (0.01 mbar) to give 3.95 g (88%) 1-(2-ethyl-butyl)-cyclohexanecarboxylic acid isopropyl ester as colorless oil, purity 97% (GC area).

Workup

  1. stirringThis orange suspension was stirred 10 min at −20° C.
  2. stirringThe resulting solution was stirred 30 min at 0° C.
  3. stirringStirring at 0° C.
  4. waitwas continued overnight and for an additional 2 h at room temperature
  5. filtrationThe white suspension was filtered
  6. washthe filter cake was washed with water and ethyl acetate
  7. washThe organic phase of the filtrate was washed with sat. aq. NaHCO3 and with aq. NaCl
  8. extractionThe aqueous phases were extracted with ethyl acetate
  9. dry with materialdried over sodium sulfate
  10. concentrationconcentrated
  11. distillationThe crude product (4.7 g) was distilled at 50° C. (0.01 mbar)

Sources & evidence

ORD record
ord-512e82baf81e40518714c5c0c9382ec4
Source dataset
uspto-grants-2011_12
Patent number
US08071803B2

Reaction notes

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