3,6-Dichloropyridazine → HCID 19095533, compound

HRID 359431Notes

Reaction equation

HRID 359431 reaction equation
[Cl:1][C:2]1[N:3]=[N:4][C:5](Cl)=[CH:6][CH:7]=1.[N:9]1[CH:14]=[CH:13][CH:12]=[CH:11][C:10]=1[N:15]1[CH2:20][CH2:19][NH:18][CH2:17][CH2:16]1.C(=O)([O-])O.[Na+]>C(O)C>[Cl:1][C:2]1[N:3]=[N:4][C:5]([N:18]2[CH2:19][CH2:20][N:15]([C:10]3[CH:11]=[CH:12][CH:13]=[CH:14][N:9]=3)[CH2:16][CH2:17]2)=[CH:6][CH:7]=1

Participants

5

Procedure

A mixture of 3.3 parts of 3,6-dichloropyridazine, 3.3 parts of 1-(2-pyridinyl)piperazine, 1.5 parts of sodium hydrogencarbonate and 120 parts of ethanol was stirred and refluxed over weekend. The reaction mixture was evaporated. Water was added to the residue and the product was extracted with dichloromethane. The extract was dried, filtered and evaporated. The residue was purified by column chromatography over silica gel using a mixture of trichloromethane and methanol (99:1 by volume) as eluent. The pure fractions were collected and the eluent was evaporated. The residue was crystallized from a mixture of 2-propanol and tetrahydrofuran, yielding 2.5 parts (45.3%) of 3-chloro-6-[4-(2-pyridinyl)-1-piperazinyl]pyridazine; mp. 194.7° C. (compound 213).

Workup

  1. temperaturerefluxed over weekend
  2. customThe reaction mixture was evaporated
  3. additionWater was added to the residue
  4. extractionthe product was extracted with dichloromethane
  5. customThe extract was dried
  6. filtrationfiltered
  7. customevaporated
  8. customThe residue was purified by column chromatography over silica gel using
  9. additiona mixture of trichloromethane and methanol (99:1 by volume) as eluent
  10. customThe pure fractions were collected
  11. customthe eluent was evaporated
  12. customThe residue was crystallized from a mixture of 2-propanol and tetrahydrofuran

Sources & evidence

ORD record
ord-e960b7abfa4d4af3b75d6a7bcde3f857
Source dataset
uspto-grants-1991_03
Patent number
US05001125

Reaction notes

Loading…