Methylglyoxal → 1-(1-Ethoxycarbonyl-4-piperidinyl)-4-(4-fluorophenyl)-5-acetylimidazole

HRID 362617Notes

Reaction equation

HRID 362617 reaction equation
[CH:1](=O)[C:2]([CH3:4])=[O:3].[NH2:6][CH:7]1[CH2:12][CH2:11][N:10]([C:13]([O:15][CH2:16][CH3:17])=[O:14])[CH2:9][CH2:8]1.C1(C)C=CC(S([CH:27]([N+:35]#[C-:36])[C:28]2[CH:33]=[CH:32][C:31]([F:34])=[CH:30][CH:29]=2)(=O)=O)=CC=1.C([O-])([O-])=O.[K+].[K+]>CS(C)=O>[CH2:16]([O:15][C:13]([N:10]1[CH2:9][CH2:8][CH:7]([N:6]2[C:1]([C:2](=[O:3])[CH3:4])=[C:27]([C:28]3[CH:29]=[CH:30][C:31]([F:34])=[CH:32][CH:33]=3)[N:35]=[CH:36]2)[CH2:12][CH2:11]1)=[O:14])[CH3:17]

Participants

6

Procedure

To a solution of pyruvaldehyde (40% w/w solution in water, 6.6 mL, 7.8 g, 0.058 mol) in DMSO (100 mL) at ambient temperature was added ethyl 4-aminopiperidinecarboxylate (10 g,, 0.058 mol). After 10 min, α-(p-toluenesulfonyl)-4-fluorobenzylisonitrile (8.4 g, 0.029 mol) and K2CO3 (8.0 g, 0.058 mol) were added. After stirring for 18 h, the solution was partition between EtOAc and 3N HCl and the organic phase was washed with 3N HCl. The combined aqueous layers were neutralized with solid K2CO3 and extracted twice with EtOAc. The combined organics were washed with brine, dried (MgSO4) and concentrated in vacuo to give a brown oil which solidified upon standing. Flash chromatography eluting consecutively with 33%, 50% and 67% EtOAc in hexanes followed by trituration with ether afforded the title compound as a white solid; yield 3.5 g (23%).

Workup

  1. customthe solution was partition between EtOAc and 3N HCl
  2. washthe organic phase was washed with 3N HCl
  3. extractionextracted twice with EtOAc
  4. washThe combined organics were washed with brine
  5. dry with materialdried (MgSO4)
  6. concentrationconcentrated in vacuo
  7. customto give a brown oil which
  8. washFlash chromatography eluting consecutively with 33%, 50% and 67% EtOAc in hexanes

Sources & evidence

ORD record
ord-23ab4fb49a324b7b9ab3a2657f831fb4
Source dataset
uspto-grants-1999_02
Patent number
US05869660

Reaction notes

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