Dimethylformamide → 1-(2-Pyrazinyl)-4-piperidinone

HRID 1253323Notes

Reaction equation

HRID 1253323 reaction equation
Cl[C:2]1[CH:7]=[N:6][CH:5]=[CH:4][N:3]=1.C([O-])([O-])=O.[K+].[K+].O1[C:18]2([CH2:23][CH2:22][NH:21][CH2:20][CH2:19]2)[O:17]CC1.CN(C)C=O>O>[N:3]1[CH:4]=[CH:5][N:6]=[CH:7][C:2]=1[N:21]1[CH2:22][CH2:23][C:18](=[O:17])[CH2:19][CH2:20]1

Participants

6

Conditions

Temperature
100 °C

Procedure

A mixture of 20 g (0.1746 mol) of chloropyrazine, 36 g (0.260 mol) of K2CO3, 76 g (0.5308 mol) of 1,4-dioxa-8-azaspiro[4.5]decane, and 80 ml of dimethylformamide is stirred at 100° C. for 3 days. The reaction mixture is cooled, diluted with water, and extracted with ethyl acetate. The combined extracts are washed with water, dried over Na2SO4 and concentrated in vacuo. The residue, 400 ml of 10% sulfuric acid solution and 100 ml of tetrahydrofuran are stirred at ambient temperature for 4 days, diluted with water, basified (NaOH) and extracted with methylene chloride. The extracts are washed with brine, dried over Na2SO4, and concentrated in vacuo. Trituration with ether gives 8.4 g of title compound: IR (KBr) 1720 and 1580 cm-1 ; NMR (CDCl3) δ 8.24-7.88 (m, 3H), 3.98 (t, 4H), and 2.56 (t, 4H).

Workup

  1. temperatureThe reaction mixture is cooled
  2. extractionextracted with ethyl acetate
  3. washThe combined extracts are washed with water
  4. dry with materialdried over Na2SO4
  5. concentrationconcentrated in vacuo
  6. stirringThe residue, 400 ml of 10% sulfuric acid solution and 100 ml of tetrahydrofuran are stirred at ambient temperature for 4 days
  7. additiondiluted with water
  8. extractionextracted with methylene chloride
  9. washThe extracts are washed with brine
  10. dry with materialdried over Na2SO4
  11. concentrationconcentrated in vacuo

Sources & evidence

ORD record
ord-6e77f6040e764c5d8af38d60d3066616
Source dataset
uspto-grants-1988_05
Patent number
US04748246

Reaction notes

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