5-Bromo-2-hydrazinopyridine → HCID 90011163, compound

HRID 1481490Notes

Reaction equation

HRID 1481490 reaction equation
[Br:1][C:2]1[CH:3]=[CH:4][C:5]([N:8]2[C:12]([CH:13]3[CH2:15][CH2:14]3)=[CH:11][C:10]([C:16]([O:18][CH2:19]C)=O)=[N:9]2)=[N:6][CH:7]=1.C1(C(=O)CC(=O)C(OCC)=[O:28])CC1.BrC1C=C[C:38]([NH:41][NH2:42])=NC=1>C(O)(=O)C>[Br:1][C:2]1[CH:3]=[CH:4][C:5]([N:8]2[C:12]([CH:13]3[CH2:14][CH2:15]3)=[CH:11][C:10]([C:16]3[O:18][C:19](=[O:28])[N:41]([CH3:38])[N:42]=3)=[N:9]2)=[N:6][CH:7]=1

Participants

5

Reactant 3

HCID 115356995-Bromo-2-hydrazinopyridineHCID 16779961Ethyl 4-cyclopropyl-2,4-dioxobutanoateHCID 90011395HCID 90011395, compound

Product 1

HCID 90011163HCID 90011163, compoundYield 43%

Reagents, catalysts & solvents 1

HCID 176Acetic AcidSolvent

Procedure

Step-1: Ethyl 1-(5-bromopyridin-2-yl)-5-cyclopropyl-1H-pyrazole-3-carboxylate: To a stirred solution of ethyl 4-cyclopropyl-2,4-dioxobutanoate (0.378 g, 2.05 mmol) in acetic acid (5 mL) was added 5-bromo-2-hydrazinylpyridine (386 mg, 2.05 mmol) at room temperature and the resulting mixture was refluxed for 2 h. The reaction was then cooled to room temperature and the solvent was evaporated under vacuum. The crude product was purified by flash column chromatography (silica gel, ethyl acetate-hexane system as eluent) to afford 300 mg (43%) of the title compound as pale yellow syrup. 1HNMR (400 MHz, CDCl3) δ 8.55 (d, J=2.0 Hz, 1H), 7.98 (dd, J=2.0 & 8.0 Hz, 1H), 7.87 (d, J=8.0 Hz, 1H), 6.50 (s, 1H), 4.41 (q, J=7.0 Hz, 2H), 2.70-2.64 (m, 1H), 1.40 (t, J=7.0 Hz, 3H), 1.05-1.00 (m, 2H), 0.75-0.71 (m, 2H); ESI-MS (m/z) 336, 338 [(MH)+Br79,81].

Workup

  1. temperaturethe resulting mixture was refluxed for 2 h
  2. customthe solvent was evaporated under vacuum
  3. customThe crude product was purified by flash column chromatography (silica gel, ethyl acetate-hexane system as eluent)

Sources & evidence

ORD record
ord-5a3776529b204672823b8f9ce9778fcc
Source dataset
uspto-grants-2016_08
Patent number
US09409898B2

Reaction notes

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