1-Isopropylhydrazine hydrochloride → 9-Bromo-2-(2-isopropyl-2H-[1,2,4]triazol-3-yl)-4,5-dihydro-6-oxa-1,10b-diaza-benzo[e]azulene

HRID 2044292Notes

Reaction equation

HRID 2044292 reaction equation
C[N:2](C)[CH:3]=[N:4][C:5]([C:7]1[CH:8]=[C:9]2[N:15]([N:16]=1)[C:14]1[CH:17]=[C:18]([Br:21])[CH:19]=[CH:20][C:13]=1[O:12][CH2:11][CH2:10]2)=O.Cl.[CH:24]([NH:27]N)([CH3:26])[CH3:25]>C(O)(=O)C>[Br:21][C:18]1[CH:19]=[CH:20][C:13]2[O:12][CH2:11][CH2:10][C:9]3[N:15]([N:16]=[C:7]([C:5]4[N:27]([CH:24]([CH3:26])[CH3:25])[N:2]=[CH:3][N:4]=4)[CH:8]=3)[C:14]=2[CH:17]=1

Participants

4

Conditions

Temperature
110 °C

Procedure

A mixture of 9-bromo-4,5-dihydro-6-oxa-1,10b-diaza-benzo[e]azulene-2-carboxylic acid 1-dimethylaminomethylideneamide (1.27 g, 3.5 mmol), isopropylhydrazine hydrochloride (0.48 g, 4.37 mmol) and glacial acetic acid (6 mL) was heated at 110° C. for 6.5 h, then cooled and concentrated in vacuo. The resultant residue was dissolved in aqueous sodium bicarbonate and DCM and the phases were separated. The aqueous phase was extracted several times with DCM, the combined organic extracts dried (MgSO4) and concentrated in vacuo. The resultant residue was subjected to flash chromatography (SiO2, gradient 30 to 70% ethyl acetate in cyclohexane) to give 9-Bromo-2-(2-isopropyl-2H-[1,2,4]triazol-3-yl)-4,5-dihydro-6-oxa-1,10b-diaza-benzo[e]azulene (0.99 g, 76%). LCMS: RT=5.07 min, M+H+=374/376. 1H NMR δ (ppm) (CDCl3): 8.07 (1H, d, J=2.41 Hz), 7.96 (1H, s), 7.39 (1H, dd, J=8.63, 2.43 Hz), 7.08 (1H, d, J=8.63 Hz), 6.91 (1H, s), 5.73-5.65 (1H, m), 4.53 (2H, t, J=5.91 Hz), 3.18 (2H, t, J=5.91 Hz), 1.60 (6H, d, J=6.62 Hz)

Workup

  1. temperaturecooled
  2. concentrationconcentrated in vacuo
  3. dissolutionThe resultant residue was dissolved in aqueous sodium bicarbonate
  4. customDCM and the phases were separated
  5. extractionThe aqueous phase was extracted several times with DCM
  6. dry with materialthe combined organic extracts dried (MgSO4)
  7. concentrationconcentrated in vacuo

Sources & evidence

ORD record
ord-db9eef3ad6ef49a3bb0c84882e177539
Source dataset
uspto-grants-2013_11
Patent number
US08586574B2

Reaction notes

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