Réaction #674306

ord-24c64029ca7446e092cc7bea4db3c609

Équation de réaction

CCOCC
Ether
CCOC(=O)Cl
Ethyl chloroformate
N#CC1CCC(OCc2ccccc2)CC1
4-(benzyloxy)cyclohexanecarbonitrile
CC(C)[N-]C(C)C.[Li+]
LDA
CCOC(=O)C1(C#N)CCC(OCc2ccccc2)CC1
ethyl 4-(benzyloxy)-1-cyanocyclohexanecarboxylate
Rendement 33.6%

Solvants

Conditions de réaction

Température
-78°CELSIUS
Conditions détaillées
See reaction.notes.procedure_details.

Traitement

  1. 1
    workup.STIRRINGThe solution was stirred at −78° C.
  2. 2
    Températureto warm to room temperature slowly
  3. 3
    workup.STIRRINGstirred overnight
  4. 4
    AutreThe reaction was quenched by addition of H2O (20 mL), HCl (1.0 N, 20 mL)
  5. 5
    ExtractionIt was then extracted with EtOAc (3×40 mL)
  6. 6
    LavageThe combined organic solution was washed with brine (50 mL)
  7. 7
    Séchagedried over anhydrous Na2SO4
  8. 8
    Concentrationconcentrated
  9. 9
    Autreto give pale yellow residue
  10. 10
    workup.STIRRINGstirred for 5 min
  11. 11
    Filtrationfiltered
  12. 12
    Autreto remove the white solid
  13. 13
    ConcentrationThe ethereal solution was concentrated
  14. 14
    Autreto give the yellow oil which
  15. 15
    Autrewas purified by CombiFlash (25 g silica gel column, EtOAc/Hexane: 0-20%)

Mode opératoire

To a solution of 4-(benzyloxy)cyclohexanecarbonitrile (1.26 g, 5.85 mmol, 1.0 equiv) in THF (dry, 30 mL) was added a solution of LDA (3.95 mL, 2.0 M Heptane/THF/toluene, 1.35 equiv) dropwise at −78° C. under N2. The resulting yellow solution was stirred at −78° C. for 2 hrs. Ethyl chloroformate (2.79 mL, 29.26 mmol, 5.0 equiv) was then added by syringe dropwise. The solution was stirred at −78° C. and allowed to warm to room temperature slowly and stirred overnight. The reaction was quenched by addition of H2O (20 mL), HCl (1.0 N, 20 mL). It was then extracted with EtOAc (3×40 mL). The combined organic solution was washed with brine (50 mL), dried over anhydrous Na2SO4 and then concentrated to give pale yellow residue. Ether (40 mL) was added and stirred for 5 min, filtered to remove the white solid. The ethereal solution was concentrated to give the yellow oil which was purified by CombiFlash (25 g silica gel column, EtOAc/Hexane: 0-20%) to afford 565 mg (yield 33%) of ethyl 4-(benzyloxy)-1-cyanocyclohexanecarboxylate as a pale yellow oil.

Source

DOI: 10.6084/m9.figshare.5104873.v1Brevet: US09226923B2uspto-grants-2016_01