Acetic Acid → 7-(2,4-Dichloro-phenyl)-3-ethyl-2-methyl-4,5,6,7-tetrahydro-2H-pyrazolo[3,4-b]pyridine

HRID 2113788Notes

Reaction equation

HRID 2113788 reaction equation
[Cl:1][C:2]1[CH:7]=[C:6]([Cl:8])[CH:5]=[CH:4][C:3]=1[N:9]1[CH2:14][CH2:13][CH2:12][C:11]2=[C:15]([CH:19]=[CH2:20])[N:16]([CH3:18])[N:17]=[C:10]12.N(C([O-])=O)=NC([O-])=O.[K+].[K+].C(O)(=O)C>CO>[Cl:1][C:2]1[CH:7]=[C:6]([Cl:8])[CH:5]=[CH:4][C:3]=1[N:9]1[CH2:14][CH2:13][CH2:12][C:11]2=[C:15]([CH2:19][CH3:20])[N:16]([CH3:18])[N:17]=[C:10]12

Participants

5

Reactant 3

HCID 176Acetic Acid2×HCID 6096233Potassium diazene-1,2-dicarboxylate2×HCID 598115207-(2,4-dichloro-phenyl)-2-methyl-3-vinyl-4,5,6,7-tetrahydro-2H-pyrazolo[3,4-b]pyridine

Product 1

HCID 598115237-(2,4-Dichloro-phenyl)-3-ethyl-2-methyl-4,5,6,7-tetrahydro-2H-pyrazolo[3,4-b]pyridine

Reagents, catalysts & solvents 1

HCID 887MethanolSolvent3×

Procedure

To a solution of 7-(2,4-dichloro-phenyl)-2-methyl-3-vinyl-4,5,6,7-tetrahydro-2H-pyrazolo[3,4-b]pyridine (3-7; 0.046 g, 0.15 mmol) in 2 mL of methanol was added dipotassium azodicarboxylate (0.174 g, 0.90 mmol) [prepared according to D. J. Pasto and R. J. Taylor, Organic Reactions 1991 40:91]. To the yellow suspension was added acetic acid (0.102 mL, 1.80 mmol) in 2 mL of methanol over 40 minutes. The reaction mixture was again treated with dipotassium azodicarboxylate (0.087 g, 0.45 mmol) and then acetic acid (0.051 mL, 0.90 mmol) in 1 mL of methanol over 20 nm. After 3 h at room temperature, the solvent was evaporated, the residue was treated with 10 mL of saturated sodium bicarbonate solution, extracted three times with 25 mL portions of dichloromethane, dried over magnesium sulfate, and evaporated to afford 41 mg of crude product. The crude product was purified by silica gel column chromatography eluting with 0 to 15% ethyl acetate/hexane which afforded 30 mg (65% theory) of 4-6 as a colorless oil: ms (M+H)+=310.

Workup

  1. customthe solvent was evaporated
  2. additionthe residue was treated with 10 mL of saturated sodium bicarbonate solution
  3. extractionextracted three times with 25 mL portions of dichloromethane
  4. dry with materialdried over magnesium sulfate
  5. customevaporated
  6. customto afford 41 mg of crude product
  7. customThe crude product was purified by silica gel column chromatography
  8. washeluting with 0 to 15% ethyl acetate/hexane which

Sources & evidence

ORD record
ord-4d7424b7128e4dca895cce1735779b69
Source dataset
uspto-grants-2008_10
Patent number
US07432283B2

Reaction notes

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