Dimethylformamide → 7,8-Dimethoxy-2-(4-nitrophenyl)-4,5-dihydro-2H-benzo[g]indazole

HRID 41950Notes

Reaction equation

HRID 41950 reaction equation
[CH3:1][O:2][C:3]1[CH:4]=[C:5]2[C:10](=[CH:11][C:12]=1[O:13][CH3:14])/[C:9](=[N:15]/[NH:16][C:17]1[CH:22]=[CH:21][C:20]([N+:23]([O-:25])=[O:24])=[CH:19][CH:18]=1)/[CH2:8][CH2:7][CH2:6]2.[CH3:26]N(C=O)C>>[CH3:1][O:2][C:3]1[C:12]([O:13][CH3:14])=[CH:11][C:10]2[C:9]3[C:8](=[CH:26][N:16]([C:17]4[CH:22]=[CH:21][C:20]([N+:23]([O-:25])=[O:24])=[CH:19][CH:18]=4)[N:15]=3)[CH2:7][CH2:6][C:5]=2[CH:4]=1

Participants

3

Reactant 2

HCID 6228DimethylformamideHCID 87138751N-[(E)-(6,7-dimethoxy-3,4-dihydro-2H-naphthalen-1-ylidene)amino]-4-nitroaniline

Product 1

HCID 667602277,8-Dimethoxy-2-(4-nitrophenyl)-4,5-dihydro-2H-benzo[g]indazoleYield 54%

Conditions

Temperature
0 °C

Procedure

Phosphorous oxytrichloride (0.2 mL) was added, over a period of 0.5 h, to a magnetically solution of (E)-1-[6,7-dimethoxy-3,4-dihydronaphthalen-1(2H)-ylidene]-2-(4-nitro-phenyl)hydrazine (56 mg, 0.16 mmol) in DMF (5 mL) maintained at 0° C. under a nitrogen atmosphere. The ensuing mixture was allowed to warm to 18° C. and left stirring at this temperature for 1 h then heated to 65° C. and stirred at this temperature for a further 16 h. The hot reaction mixture was poured onto crushed ice and the crystals so-formed were collected by filtration. Recrystallisation (ethyl acetate/hexane) of this material then afforded the title compound (31 mg, 54%) as orange crystals, m.p. 150° C. (with decomposition).

Workup

  1. temperatureto warm to 18° C.
  2. waitleft
  3. temperaturethen heated to 65° C.
  4. stirringstirred at this temperature for a further 16 h
  5. additionThe hot reaction mixture was poured
  6. customonto crushed ice
  7. customthe crystals so-formed
  8. filtrationwere collected by filtration
  9. customRecrystallisation (ethyl acetate/hexane) of this material

Sources & evidence

ORD record
ord-0ebe7193a88448f98cea6f82c75f13a8
Source dataset
uspto-grants-2013_09
Patent number
US08536157B2

Reaction notes

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