Acetic Acid → 1H-Indazole

HRID 1658833Notes

Reaction equation

HRID 1658833 reaction equation
[N:1]([C:4]1[C:9]([CH:10]=O)=[CH:8][C:7](OC)=[C:6](OC)[CH:5]=1)=[N+:2]=[N-].NC1C=CC=CC=1.C(O)(=O)C>CN(C)C=O>[NH:1]1[C:4]2[C:9](=[CH:8][CH:7]=[CH:6][CH:5]=2)[CH:10]=[N:2]1

Participants

5

Reactant 3

HCID 176Acetic AcidHCID 6115AnilineHCID 11344785Benzaldehyde, 2-azido-4,5-dimethoxy-

Product 1

HCID 92211H-IndazoleYield 169.3%

Reagents, catalysts & solvents 1

HCID 6228DimethylformamideSolvent

Procedure

A solution containing 51.8 g (0.25 mole) 6-azidoveratraldehyde (Example XII), 26.0 g (0.28 mole) aniline, 4 ml galcial acetic acid, and 300 ml dimethylformamide was stirred at 90-100° for 1 hr, then refluxed for 1 hr until the gaseous evolution was complete. After the mixture was cooled and poured slowly in 1.5 l. iced water, the product was filtered, washed with two 150 ml portions cold water, and air dried to give 50 g of crude indazole, m.p. 130°-138°. Recrystallization from ethyl acetate - hexane followed by ethyl acetate gave 26 g (41%) of the product, m.p. 149°-152°. Recrystallization from ethyl acetate - hexane gave the analytical sample, m.p. 149°-152°.

Workup

  1. temperaturerefluxed for 1 hr until the gaseous evolution
  2. temperatureAfter the mixture was cooled
  3. additionpoured slowly in 1.5 l
  4. filtrationiced water, the product was filtered
  5. washwashed with two 150 ml portions cold water, and air
  6. customdried

Sources & evidence

ORD record
ord-c2d393a9c5094bedbdff4342de3f1aa1
Source dataset
uspto-grants-1976_06
Patent number
US03966760

Reaction notes

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