Phosphorus oxychloride → 7-Chloro-3-(4-chlorophenyl)-2-(2,4-dichlorophenyl)-2H-pyrazolo[3,4-c]pyridine

HRID 915833Notes

Reaction equation

HRID 915833 reaction equation
C([N:8]1[CH:13]=[CH:12][C:11]2=[C:14]([C:25]3[CH:30]=[CH:29][C:28]([Cl:31])=[CH:27][CH:26]=3)[N:15]([C:17]3[CH:22]=[CH:21][C:20]([Cl:23])=[CH:19][C:18]=3[Cl:24])[N:16]=[C:10]2[C:9]1=O)C1C=CC=CC=1.O=P(Cl)(Cl)[Cl:35]>>[Cl:35][C:9]1[C:10]2=[N:16][N:15]([C:17]3[CH:22]=[CH:21][C:20]([Cl:23])=[CH:19][C:18]=3[Cl:24])[C:14]([C:25]3[CH:30]=[CH:29][C:28]([Cl:31])=[CH:27][CH:26]=3)=[C:11]2[CH:12]=[CH:13][N:8]=1

Participants

3

Reactant 2

HCID 24813Phosphorus oxychlorideHCID 112369906-Benzyl-3-(4-chlorophenyl)-2-(2,4-dichlorophenyl)-2,6-dihydropyrazolo[3,4-c]pyridin-7-one

Product 1

HCID 589595107-Chloro-3-(4-chlorophenyl)-2-(2,4-dichlorophenyl)-2H-pyrazolo[3,4-c]pyridineYield 58%

Procedure

A stirred suspension of 6-benzyl-3-(4-chlorophenyl)-2-(2,4-dichlorophenyl)-2,6-dihydropyrazolo[3,4-c]pyridin-7-one (I-1A-1b; 153 mg, 0.32 mmol) in POCl3 (3.5 ml) was heated to reflux for 48 hr. After the reaction was cooled and concentrated, in vacuo, an ethyl acetate solution of the residue was washed with saturated aqueous NaHCO3 and then brine. The solution was dried (Na2SO4), concentrated, in vacuo, and then purified on a Biotage™ Flash 12M column using 0-15-30% ethyl acetate in hexanes to afford I-1A-1c as an off-white solid (75 mg, 58%): +ESI MS (M+1) 408.0; 1H NMR (400 MHz, CD2Cl2) δ 8.01 (d, J=5.8 Hz, 1H), 7.57-7.53 (m, 3H), 7.47 (dd, J=8.7, 2.1 Hz, 1H), 7.41 (d, J=8.7 Hz, 2H), 7.27 (d, J=8.7 Hz, 2H).

Workup

  1. temperaturewas heated
  2. temperatureto reflux for 48 hr
  3. temperatureAfter the reaction was cooled
  4. concentrationconcentrated, in vacuo
  5. washan ethyl acetate solution of the residue was washed with saturated aqueous NaHCO3
  6. dry with materialThe solution was dried (Na2SO4)
  7. concentrationconcentrated, in vacuo
  8. custompurified on a Biotage™ Flash 12M column

Sources & evidence

ORD record
ord-87b62fdcc61045c681d6720f05a973ca
Source dataset
uspto-grants-2007_09
Patent number
US07268133B2

Reaction notes

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