Acetic Acid → 6-Chloro-3-methyl-[1,2,4]triazolo[4,3-b]pyridazine-8-carboxylic acid

HRID 521565Notes

Reaction equation

HRID 521565 reaction equation
[Cl:1][C:2]1[N:7]=[N:6][C:5]([NH:8][NH2:9])=[C:4]([C:10]([OH:12])=[O:11])[CH:3]=1.[C:13](O)(=O)[CH3:14]>>[Cl:1][C:2]1[CH:3]=[C:4]([C:10]([OH:12])=[O:11])[C:5]2[N:6]([C:13]([CH3:14])=[N:9][N:8]=2)[N:7]=1

Participants

3

Reactant 2

HCID 176Acetic AcidHCID 205385786-Chloro-3-hydrazinylpyridazine-4-carboxylic acid

Product 1

HCID 729431896-Chloro-3-methyl-[1,2,4]triazolo[4,3-b]pyridazine-8-carboxylic acidYield 72.5%

Conditions

Temperature
100 °C

Procedure

A suspension of starting material 6-chloro-3-hydrazinylpyridazine-4-carboxylic acid (4.80 g, 26 mmol) in acetic acid (100 mL) was heated at 100° C. for 3 hours. The mixture was cooled to room temperature, concentrated in vacuum to give the crude product, which was washed by PE (50 mL) first, then recrystallized from MeOH to give product 6-chloro-3-methyl-[1,2,4]triazolo[4,3-b]pyridazine-8-carboxylic acid as a yellow solid (4.00 g, 72.5%). 1H NMR (300 MHz, DMSO) δ: 7.2 (s, 1H), 2.66 (s, 3H). LRMS (M+H+) m/z: calcd 213; found 213.

Workup

  1. temperatureThe mixture was cooled to room temperature
  2. concentrationconcentrated in vacuum
  3. customto give the crude product, which
  4. washwas washed by PE (50 mL) first
  5. customrecrystallized from MeOH

Sources & evidence

ORD record
ord-63f4258360104d489e53c1fceaab83c5
Source dataset
uspto-grants-2016_05
Patent number
US09328117B2

Reaction notes

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