Potassium Carbonate → 2-(2,6-Dichlorophenyl)-7-methyl-2H-pyrazolo[4,3-c]pyridine-5-oxide

HRID 626776Notes

Reaction equation

HRID 626776 reaction equation
CB1OB(C)OB(C)O1.Br[C:11]1[C:12]2[C:13](=[CH:18][N:19]([C:21]3[C:26]([Cl:27])=[CH:25][CH:24]=[CH:23][C:22]=3[Cl:28])[N:20]=2)[CH:14]=[N+:15]([O-:17])[CH:16]=1.[C:29](=O)([O-])[O-].[K+].[K+]>O1CCOCC1.C1C=CC([P]([Pd]([P](C2C=CC=CC=2)(C2C=CC=CC=2)C2C=CC=CC=2)([P](C2C=CC=CC=2)(C2C=CC=CC=2)C2C=CC=CC=2)[P](C2C=CC=CC=2)(C2C=CC=CC=2)C2C=CC=CC=2)(C2C=CC=CC=2)C2C=CC=CC=2)=CC=1>[Cl:28][C:22]1[CH:23]=[CH:24][CH:25]=[C:26]([Cl:27])[C:21]=1[N:19]1[CH:18]=[C:13]2[CH:14]=[N+:15]([O-:17])[CH:16]=[C:11]([CH3:29])[C:12]2=[N:20]1

Participants

6

Reactant 3

HCID 11430Potassium CarbonateHCID 574072Trimethylboroxine2×HCID 696713397-Bromo-2-(2,6-dichlorophenyl)-2H-pyrazolo[4,3-c]pyridine-5-oxide

Product 1

HCID 696710992-(2,6-Dichlorophenyl)-7-methyl-2H-pyrazolo[4,3-c]pyridine-5-oxideYield 69%

Reagents, catalysts & solvents 2

HCID 178418397HCID 178418397, compoundCatalystHCID 312751,4-DioxaneSolvent

Conditions

Temperature
80 °C

Procedure

Trimethylboroxine (0.348 mL, 2.5 mmol) was added to a suspension of 7-bromo-2-(2,6-dichlorophenyl)-2H-pyrazolo[4,3-c]pyridine-5-oxide (720 mg, 2.0 mmol), potassium carbonate (829 mg, 6.0 mmol) and Pd(PPh3)4 (228 mg, 0.2 mmol) in dioxane (11 mL) and the reaction mixture was heated at 80° C., under an atmosphere of nitrogen overnight. Additional trimethylboroxine (0.278 mL) was added and the reaction mixture was heated at 80° C. for another 2 hours. The resultant mixture was cooled to room temperature and filtered. The solid was washed with ethyl acetate and methanol (9:1). The filtrate was concentrated under reduced pressure to give a brown solid. This was purified by silica gel flash chromatography (0-20% methanol in ethyl acetate) to afford the title compound as a pale yellow solid (405 mg, 69% yield). LCMS (Method F): RT=2.30 min, m/z: 294 [M+H+].

Workup

  1. temperaturethe reaction mixture was heated at 80° C. for another 2 hours
  2. filtrationfiltered
  3. washThe solid was washed with ethyl acetate and methanol (9:1)
  4. concentrationThe filtrate was concentrated under reduced pressure
  5. customto give a brown solid
  6. customThis was purified by silica gel flash chromatography (0-20% methanol in ethyl acetate)

Sources & evidence

ORD record
ord-597e30971d464345aabea35b6e0a6bd6
Source dataset
uspto-grants-2016_04
Patent number
US09309240B2

Reaction notes

Loading…