tert-Butylhydrazine monohydrochloride → 2-Tert-butyl-4,5-dichloro-2,3-dihydropyridazin-3-one

HRID 1241790Notes

Reaction equation

HRID 1241790 reaction equation
[C:1](O)(=O)/[C:2](=[C:4](\[CH:6]=[O:7])/[Cl:5])/[Cl:3].Cl.[C:11]([NH:15][NH2:16])([CH3:14])([CH3:13])[CH3:12]>CO>[C:11]([N:15]1[C:6](=[O:7])[C:4]([Cl:5])=[C:2]([Cl:3])[CH:1]=[N:16]1)([CH3:14])([CH3:13])[CH3:12]

Participants

4

Reactant 2

HCID 81889tert-Butylhydrazine monohydrochlorideHCID 2771871Mucochloric Acid

Product 1

HCID 27822252-Tert-butyl-4,5-dichloro-2,3-dihydropyridazin-3-one

Reagents, catalysts & solvents 1

HCID 887MethanolSolvent

Procedure

A solution of mucochloric acid (33.8 g, 200 mmol) and tert.-butylhydrazine hydrochloride (24.9 g, 200 mmol) in methanol (400 mL) was stirred at reflux overnight. Methanol was removed in vacuo and the residue was partitioned between ether and water. The organic layer was dried over MgSO4 and filtered. The filtrate was concentrated in vacuo and the residue was purified by column chromatography (silica gel, 100% hexanes). Product-containing fractions were combined and the title compound was crystallized from ether/hexanes (yield: 10.0 g, 22.6%). mp 63–64° C. 1H NMR (300 MHz, CDCl3) δ 1.65 (s, 9H), 7.73 (s, 1H). MS (DCI/NH3) m/z 221 (M+H)+, 238 (M+NH4)+.

Workup

  1. temperatureat reflux overnight
  2. customMethanol was removed in vacuo
  3. customthe residue was partitioned between ether and water
  4. dry with materialThe organic layer was dried over MgSO4
  5. filtrationfiltered
  6. concentrationThe filtrate was concentrated in vacuo
  7. customthe residue was purified by column chromatography (silica gel, 100% hexanes)
  8. customthe title compound was crystallized from ether/hexanes (yield: 10.0 g, 22.6%)

Sources & evidence

ORD record
ord-ed61338592904db08de51b9ea4c0655c
Source dataset
uspto-grants-2006_10
Patent number
US07115591B2

Reaction notes

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