O-Phenylenediamine → 3-(1H-benzo[d]imidazol-2-yl)-5-nitro-1-(tetrahydro-2H-pyran-2-yl)-1H-indazole

HRID 1047527Notes

Reaction equation

HRID 1047527 reaction equation
[N+:1]([C:4]1[CH:5]=[C:6]2[C:10](=[CH:11][CH:12]=1)[N:9]([CH:13]1[CH2:18][CH2:17][CH2:16][CH2:15][O:14]1)[N:8]=[C:7]2[CH:19]=O)([O-:3])=[O:2].[C:21]1([NH2:28])[CH:26]=[CH:25][CH:24]=[CH:23][C:22]=1[NH2:27].S(=O)(O)[O-].[Na+]>C1COCC1.Cl.C(OCC)(=O)C>[NH:27]1[C:22]2[CH:23]=[CH:24][CH:25]=[CH:26][C:21]=2[N:28]=[C:19]1[C:7]1[C:6]2[C:10](=[CH:11][CH:12]=[C:4]([N+:1]([O-:3])=[O:2])[CH:5]=2)[N:9]([CH:13]2[CH2:18][CH2:17][CH2:16][CH2:15][O:14]2)[N:8]=1

Participants

7

Reactant 3

HCID 7243O-PhenylenediamineHCID 23665763Sodium BisulfiteHCID 86673211HCID 86673211, compound

Product 1

HCID 1363522443-(1H-benzo[d]imidazol-2-yl)-5-nitro-1-(tetrahydro-2H-pyran-2-yl)-1H-indazoleYield 50%

Reagents, catalysts & solvents 3

HCID 313Hydrochloric AcidCatalystHCID 8028TetrahydrofuranSolventHCID 8857Ethyl AcetateSolvent

Procedure

5-Nitro-1-(tetrahydro-2H-pyran-2-yl)-1H-indazole-3-carbaldehyde (100 mg, 0.363 mmol) and o-phenylene diamine (40 mg, 0.369 mmol) were dissolved in dry THF (8 mL), and 2N HCl (1 drop) was added. The solution was heated at a gentle reflux for 30 min and then 1N sodium bisulfite (1 mL) was added. After overnight at reflux, the solution was cooled to room temperature, and diluted with ethyl acetate (40 mL). The mixture was washed with water and brine, dried over Na2SO4, and concentrated. Purification by flash chromatography (20% ethyl acetate/hexane) afforded the title compound as a pale yellow solid in a 50% yield. 1H NMR (400 MHz, CDCl3): δ 9.82 (s, 1H), 9.60 (d, 1H, J=2.4 Hz), 8.30 (dd, 1H, J=2.0 & 9.2 Hz), 7.87 (m, 1H), 7.66 (d, 1H, J=9.2 Hz), 7.47 (m, 1H), 7.28 (m, 2H), 5.77 (dd, 1H, J=2.4 and 8.8 Hz), 4.00 (m, 1H), 3.76 (m, 1H), 2.53 (m, 1H), 2.13 (m, 2H), 1.77 (m, 3H).

Workup

  1. temperatureThe solution was heated at
  2. temperaturea gentle reflux for 30 min
  3. temperatureAfter overnight at reflux
  4. washThe mixture was washed with water and brine
  5. dry with materialdried over Na2SO4
  6. concentrationconcentrated
  7. customPurification by flash chromatography (20% ethyl acetate/hexane)

Sources & evidence

ORD record
ord-f62f5609eb854a14ab6804322b4d1bbd
Source dataset
uspto-grants-2013_10
Patent number
US08569511B2

Reaction notes

Loading…