Cyclohexanone → 1-Cyclohexylpyrrolidine

HRID 1167033

Reaction equation

HRID 1167033 reaction equation
[NH:1]1[CH2:5][CH2:4][CH2:3][CH2:2]1.[C:6]1(=O)[CH2:11][CH2:10][CH2:9][CH2:8][CH2:7]1.S([O-])([O-])(=O)=O.[Mg+2]>CCCCCC>[CH:6]1([N:1]2[CH2:5][CH2:4][CH2:3][CH2:2]2)[CH2:11][CH2:10][CH2:9][CH2:8][CH2:7]1

Participants

5

Reactant 3

HCID 7967CyclohexanoneHCID 24083Sulfuric acid magnesium salt (1:1)HCID 31268Pyrrolidine

Product 1

HCID 1390641-Cyclohexylpyrrolidine

Reagents, catalysts & solvents 1

HCID 8058HexaneSolvent

Procedure

The structure-directing agent (SDA) is synthesized using the reaction sequence described in the scheme below. A three neck 3 000-ml flask is charged with 100 gm (1.4 mole) of pyrrolidine, 50 gm of cyclohexanone (0.51 mole) and 1000 ml anhydrous hexane. To the resulting solution, 122 gm (1.022 mole) of anhydrous magnesium sulfate is added and the mixture is mechanically stirred and heated at reflux (the reaction is monitored by NMR analysis) for 96 hrs. The reaction mixture is filtered through a fritted glass funnel. The filtrate is concentrated under reduced pressure on a rotary evaporator to give 75 gm of a clear (yellow-tinted) oily substance. 1H-NMR and 13C-NMR spectra are acceptable for the desired product 1-(1-pyrrolidino)cyclohexene. Saturation of 1-(1-pyrrolidino)cyclohexene, to give N-cyclohexylpyrrolidine, is accomplished in quantitative yield by hydrogenation in ethanol at a 55 psi pressure of hydrogen gas in the presence of 10% Pd on activated carbon.

Workup

  1. customThe structure-directing agent (SDA) is synthesized
  2. temperatureheated
  3. temperatureat reflux (the reaction
  4. customfor 96 hrs
  5. filtrationThe reaction mixture is filtered through a fritted glass funnel
  6. concentrationThe filtrate is concentrated under reduced pressure on a rotary evaporator
  7. customto give 75 gm of a clear (yellow-tinted) oily substance

Sources & evidence

ORD record
ord-daf53d9553b44280b7361cf574f31ae2
Source dataset
uspto-grants-2003_09
Patent number
US06616830B2

Linked notes

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