2,3-Dichloro-5,6-dicyano-1,4-benzoquinone → Methyl 5-methyl-2-phenyl-7-p-tolylpyrazolo[1,5-a]pyrimidine-6-carboxylate

HRID 472814Notes

Reaction equation

HRID 472814 reaction equation
[CH3:1][C:2]1[CH:9]=[CH:8][C:5]([CH:6]=O)=[CH:4][CH:3]=1.[C:10]1([C:16]2[CH:20]=[C:19]([NH2:21])[NH:18][N:17]=2)[CH:15]=[CH:14][CH:13]=[CH:12][CH:11]=1.O=[C:23]([CH3:29])[CH2:24][C:25]([O:27][CH3:28])=[O:26].C(C1C(=O)C(Cl)=C(Cl)C(=O)C=1C#N)#N>C1COCC1.CCCCCCC.N1CCCCC1>[CH3:29][C:23]1[C:24]([C:25]([O:27][CH3:28])=[O:26])=[C:6]([C:5]2[CH:8]=[CH:9][C:2]([CH3:1])=[CH:3][CH:4]=2)[N:18]2[N:17]=[C:16]([C:10]3[CH:11]=[CH:12][CH:13]=[CH:14][CH:15]=3)[CH:20]=[C:19]2[N:21]=1

Participants

8

Reactant 4

HCID 67752,3-Dichloro-5,6-dicyano-1,4-benzoquinoneHCID 77254-MethylbenzaldehydeHCID 7757Methyl acetoacetateHCID 1366553-Amino-5-phenylpyrazole

Product 1

HCID 66693154Methyl 5-methyl-2-phenyl-7-p-tolylpyrazolo[1,5-a]pyrimidine-6-carboxylateYield 64.4%

Reagents, catalysts & solvents 3

HCID 8082PiperidineCatalystHCID 8028TetrahydrofuranSolventHCID 8900HeptaneSolvent

Procedure

To a stirred solution of 4-methylbenzaldehyde (1.2 g, 9.99 mmol), 3-phenyl-1H-pyrazol-5-amine (1.6 g, 9.99 mmol), and methyl 3-oxobutanoate (1.3 g, 10.99 mmol) in THF (80 mL) and heptane (20 mL) was added piperidine (30 mL, 0.303 mmol). The reaction mixture was heated at reflux for 20 h. The solvent was evaporated and the crude material was dissolved in CH2Cl2. DDQ (2041 mg, 8.99 mmol) was added and the mixture was stirred at room temperature for 1 h. The solvent was evaporated. Purification by silica gel chromatography provided the title compound (2.3 g, 64.4%). 1H-NMR (500 MHz, CDCl3) δ ppm 2.47 (3H, s), 2.65 (3H, s), 3.64 (3H, s), 6.93 (1H, s), 7.31-7.47 (5H, m), 7.63 (2H, d, J=7.9 Hz), 7.86-7.99 (2H, m).

Workup

  1. temperatureThe reaction mixture was heated
  2. temperatureat reflux for 20 h
  3. customThe solvent was evaporated
  4. dissolutionthe crude material was dissolved in CH2Cl2
  5. customThe solvent was evaporated
  6. customPurification by silica gel chromatography

Sources & evidence

ORD record
ord-f588f73abd2849428bb8829abd107e9a
Source dataset
uspto-grants-2014_01
Patent number
US08633200B2

Reaction notes

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