Diethyl Ether → 1,4-Dibenzyl-4-cyanopiperidine

HRID 355461Notes

Reaction equation

HRID 355461 reaction equation
[C:1]([CH:3]1[CH2:8][CH2:7][NH:6][CH2:5][CH2:4]1)#[N:2].[CH:9]([N-]C(C)C)([CH3:11])[CH3:10].[Li+].[CH2:17](Br)[C:18]1[CH:23]=[CH:22][CH:21]=[CH:20][CH:19]=1.CCOCC.[CH2:30]1[CH2:34]O[CH2:32][CH2:31]1>C1CCCCC1>[CH2:17]([N:6]1[CH2:7][CH2:8][C:3]([CH2:32][C:31]2[CH:11]=[CH:9][CH:10]=[CH:34][CH:30]=2)([C:1]#[N:2])[CH2:4][CH2:5]1)[C:18]1[CH:23]=[CH:22][CH:21]=[CH:20][CH:19]=1

Participants

7

Conditions

Temperature
-50 °C

Procedure

A solution of 15 g of 4-cyanopiperidine in 250 ml of THF is cooled to -50° C., 190 ml of a 1.5M solution of lithium diisopropylamide in cyclohexane is added dropwise and the mixture is left stirring for 30 minutes at -50° C. 34 ml of benzylbromide are then added slowly and the mixture is left stirring for 3 hours while allowing the temperature to rise to RT. The reaction mixture is poured into an ice/concentrated HCl mixture, ether is added and the precipitate formed is drained and washed with water. The precipitate is taken up in water, the mixture is alkalinized to pH 12 by adding concentrated NaOH solution and extracted with ether, the organic phase is dried over MgSO4 and the solvent is evaporated off under vacuum. 31.7 g of the expected product are obtained after crystallization in pentane, m.p.=92° C.

Workup

  1. waitthe mixture is left
  2. waitthe mixture is left
  3. stirringstirring for 3 hours
  4. customto rise to RT
  5. additionis added
  6. customthe precipitate formed
  7. washwashed with water
  8. additionby adding concentrated NaOH solution
  9. extractionextracted with ether
  10. dry with materialthe organic phase is dried over MgSO4
  11. customthe solvent is evaporated off under vacuum

Sources & evidence

ORD record
ord-02964c1ce5dc440b8b560165e012ed90
Source dataset
uspto-grants-1998_11
Patent number
US05830906

Reaction notes

Loading…