Ethanol → 2-Cyanobicyclo[2.2.1]hept-5-ene-2-carboxylic acid

HRID 1415252Notes

Reaction equation

HRID 1415252 reaction equation
[C:1]([C:3]1([C:10]([O:12]CC(C)C)=[O:11])[CH2:8][CH:7]2[CH2:9][CH:4]1[CH:5]=[CH:6]2)#[N:2].C(O)C.[OH-].[K+]>O>[C:1]([C:3]1([C:10]([OH:12])=[O:11])[CH2:8][CH:7]2[CH2:9][CH:4]1[CH:5]=[CH:6]2)#[N:2]

Participants

5

Reactant 3

HCID 702EthanolHCID 14797Potassium HydroxideHCID 21419268HCID 21419268, compound

Product 1

HCID 128738652-Cyanobicyclo[2.2.1]hept-5-ene-2-carboxylic acid

Reagents, catalysts & solvents 1

HCID 962WaterSolvent

Procedure

To a solution of 250 g (1.14 moles) isobutyl 2-cyano-5-norbornene-2-carboxylate (IBC/CPD adduct) in 1000 ml. 95% ethanol is added a solution of 112 g (1.71 moles) of potassium hydroxide (86%w) in 1000 ml. water. The solution is refluxed on a steam bath for one hour, diluted with 3500 ml. water, and extracted with 2 × 400 ml. benzene to remove any unreacted ester. The aqueous phase is acidified to pH 1 with 6 N HCl and the oily product extracted into 4 × 200 ml. chloroform. The combined extracts are backwashed with 3 × 200 ml. water (which removed the orange color), dried over anhydrous sodium sulfate, and solvent stripped to give 182.3 g (98% theory) of the crude adduct, a pale orange syrupy liquid. Crystallization from benzene/hexane gives three crops of purified 2-cyano-5-norbornene-2-carboxylic acid: (1) 89.7 g, mp 87.5°-92° C, (2) 34.2 g, mp 87.5°-96.5° C, and (3) 15.9 g, mp. 85°-90° C.

Workup

  1. temperatureThe solution is refluxed on a steam bath for one hour
  2. additiondiluted with 3500 ml
  3. extractionwater, and extracted with 2 × 400 ml
  4. custombenzene to remove any unreacted ester
  5. extractionthe oily product extracted into 4 × 200 ml
  6. customwater (which removed the orange color),
  7. dry with materialdried over anhydrous sodium sulfate, and solvent
  8. customto give 182.3 g (98% theory) of the crude adduct
  9. customCrystallization from benzene/hexane

Sources & evidence

ORD record
ord-8fb2394347af4d7bb52d47765d3d2f30
Source dataset
uspto-grants-1977_01
Patent number
US04003942

Reaction notes

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