Phosphorus oxychloride → HCID 22770496, compound

HRID 1764098Notes

Reaction equation

HRID 1764098 reaction equation
[CH2:1]([N:3]1[C:7]2=[N:8][C:9]([C:13]3[CH:18]=[CH:17][CH:16]=[CH:15][CH:14]=3)=[CH:10][C:11](O)=[C:6]2[CH:5]=[N:4]1)[CH3:2].P(Cl)(Cl)([Cl:21])=O>>[Cl:21][C:11]1[CH:10]=[C:9]([C:13]2[CH:18]=[CH:17][CH:16]=[CH:15][CH:14]=2)[N:8]=[C:7]2[N:3]([CH2:1][CH3:2])[N:4]=[CH:5][C:6]=12

Participants

3

Reactant 2

HCID 24813Phosphorus oxychlorideHCID 178463017HCID 178463017, compound

Product 1

HCID 22770496HCID 22770496, compound

Procedure

A mixture of 193.9 gms. of 1-ethyl-4-hydroxy-6-phenyl-1H-pyrazolo[3,4-b]pyridine (0.7 mol.) and 1000 ml. of phosphorus oxychloride is refluxed for 5 hours. The excess phosphorus oxychloride is removed in vacuo and the residue is treated with ice water. The mixture is then extracted three times with ether, the ether layer is separated, dried over sodium sulfate, treated with charcoal and concentrated in vacuo. The residue solidifies on cooling (142.4 gms = 79%; m.p. 43°-45° C.) and the product, 4-chloro-1-ethyl-6-phenyl-1H-pyrazolo[3,4-b]pyridine is recrystallized from hexane, m.p. 46°-48° C.

Workup

  1. additionA mixture of 193.9 gms
  2. customThe excess phosphorus oxychloride is removed in vacuo
  3. additionthe residue is treated with ice water
  4. extractionThe mixture is then extracted three times with ether
  5. customthe ether layer is separated
  6. dry with materialdried over sodium sulfate
  7. additiontreated with charcoal
  8. concentrationconcentrated in vacuo
  9. temperatureon cooling (142.4 gms = 79%; m.p. 43°-45° C.)
  10. customthe product, 4-chloro-1-ethyl-6-phenyl-1H-pyrazolo[3,4-b]pyridine is recrystallized from hexane, m.p. 46°-48° C.

Sources & evidence

ORD record
ord-8679605207d1489db3c299765c3865fd
Source dataset
uspto-grants-1978_09
Patent number
US04115394

Reaction notes

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