Ethylene Glycol → 2-Bromo-1-(2-trimethylsilylethoxymethyl)-1,5-dihydropyrrolo[2,3-d]pyridazin-4-one

HRID 2097486Notes

Reaction equation

HRID 2097486 reaction equation
C(O)CO.[Br:5][C:6]1[N:10]([CH2:11][O:12][CH2:13][CH2:14][Si:15]([CH3:18])([CH3:17])[CH3:16])[C:9]([CH:19]=O)=[C:8]([C:21]([O:23]CC)=O)[CH:7]=1.O.[NH2:27][NH2:28]>O>[Br:5][C:6]1[N:10]([CH2:11][O:12][CH2:13][CH2:14][Si:15]([CH3:18])([CH3:17])[CH3:16])[C:9]2[CH:19]=[N:27][NH:28][C:21](=[O:23])[C:8]=2[CH:7]=1

Participants

5

Reactant 3

HCID 174Ethylene GlycolHCID 24654Hydrazine hydrate (1:1)HCID 86627038Ethyl 5-bromo-2-formyl-1-(2-trimethylsilylethoxymethyl)-1H-pyrrol-3-carboxylate

Product 1

HCID 666026402-Bromo-1-(2-trimethylsilylethoxymethyl)-1,5-dihydropyrrolo[2,3-d]pyridazin-4-oneYield 74%

Reagents, catalysts & solvents 1

HCID 962WaterSolvent

Conditions

Temperature
125 °C

Procedure

To 2.1 L of ethylene glycol solution containing 430 g (1.14 mol) of ethyl 5-bromo-2-formyl-1-(2-trimethylsilylethoxymethyl)-1H-pyrrol-3-carboxylate obtained in Reference example 15-(f) was added 290 ml (5.98 mol) of hydrazine monohydrate at 60° C., and the mixture was stirred at 125° C. for 2 hours. After completion of the reaction, the reaction mixture was poured into water, and precipitated solid was collected by filtration and washed with water. The obtained crude solid was recrystallized from 3 L of a mixed solvent (toluene/cyclohexane=1/1 (V/V)) to obtain 289 g of the title compound as a beige solid. (Yield: 74%)

Workup

  1. customAfter completion of the reaction
  2. customprecipitated solid
  3. filtrationwas collected by filtration
  4. washwashed with water
  5. customThe obtained crude solid
  6. customwas recrystallized from 3 L of a mixed solvent (toluene/cyclohexane=1/1 (V/V))

Sources & evidence

ORD record
ord-fccda1841fc546ec88755217ee31673d
Source dataset
uspto-grants-2013_05
Patent number
US08450319B2

Reaction notes

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