Acetic Acid → HCID 20569894, compound

HRID 1577831Notes

Reaction equation

HRID 1577831 reaction equation
[OH:1][CH:2]1[CH2:7][CH2:6][N:5]([C:8]2[C:17]3[C:12](=[CH:13][C:14]([O:20][CH3:21])=[C:15]([O:18][CH3:19])[CH:16]=3)[CH:11]=[N:10][N:9]=2)[CH2:4][CH2:3]1.[C:22]([O:25]C(=O)C)(=[O:24])C.[C:29](O)(=[O:31])[CH3:30].[C:33](=[O:36])([O-:35])[O-].[Na+].[Na+]>O>[C:22]([OH:25])(=[O:24])[C:33]([OH:35])=[O:36].[C:29]([O:1][CH:2]1[CH2:3][CH2:4][N:5]([C:8]2[C:17]3[C:12](=[CH:13][C:14]([O:20][CH3:21])=[C:15]([O:18][CH3:19])[CH:16]=3)[CH:11]=[N:10][N:9]=2)[CH2:6][CH2:7]1)(=[O:31])[CH3:30]

Participants

6

Reactant 4

HCID 176Acetic AcidHCID 7918Acetic AnhydrideHCID 10340Sodium CarbonateHCID 205698911-(6,7-Dimethoxy-1-phthalazinyl)-4-piperidinol

Product 1

HCID 20569894HCID 20569894, compound

Reagents, catalysts & solvents 1

HCID 962WaterSolvent

Procedure

1-(4-Hydroxypiperidino)-6,7-dimethoxyphthalazine (1.45 g), (prepared as in Example 2), acetic anhydride (1.5 g) and acetic acid (12 ml) were heated together at 90° for 17 hours. The cooled solution was then diluted with water (20 ml), basified with sodium carbonate to pH 10, and extracted with chloroform (2×50 ml). The chloroform extract was washed (H2O), dried (MgSO4), and evaporated in vacuo to give a dark oil. The oil was applied to the top of a column of powdered silica (bed size 30×2.0 cm) and eluted with chloroform containing increasing percentages (up to 30%) of methanol. Of fifteen fractions (each of 100 ml) collected, fractions 11-13 were combined and evaporated in vacuo to give an oily residue which was triturated with ether (60 ml). After removing insoluble material by filtration, the ethereal solution was treated with ethereal oxalic acid to pH 4 to precipitate the gelatinous oxalate salt. Recrystallization from ethanol gave pink crystals of 1 -(4-acetoxypiperidino)-6,7-dimethoxy phthalazine monooxalate (120 mg), m.p. 212°-13°.

Workup

  1. extractionextracted with chloroform (2×50 ml)
  2. extractionThe chloroform extract
  3. washwas washed (H2O)
  4. dry with materialdried (MgSO4)
  5. customevaporated in vacuo
  6. customto give a dark oil
  7. washeluted with chloroform containing
  8. temperatureincreasing percentages (up to 30%) of methanol
  9. customOf fifteen fractions (each of 100 ml) collected
  10. customevaporated in vacuo
  11. customto give an oily residue which
  12. customwas triturated with ether (60 ml)
  13. customAfter removing insoluble material
  14. filtrationby filtration
  15. additionthe ethereal solution was treated with ethereal oxalic acid to pH 4
  16. customto precipitate the gelatinous oxalate salt
  17. customRecrystallization from ethanol

Sources & evidence

ORD record
ord-fa35b84ed1cb49f8b0ba589fa4513dc1
Source dataset
uspto-grants-1981_09
Patent number
US04289772

Reaction notes

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