Methylhydrazine → 4-(4-Bromophenyl)-2-methylphthalazin-1-one

HRID 54990Notes

Reaction equation

HRID 54990 reaction equation
[Br:1][C:2]1[CH:18]=[CH:17][C:5]([C:6]([C:8]2[CH:16]=[CH:15][CH:14]=[CH:13][C:9]=2[C:10](O)=[O:11])=O)=[CH:4][CH:3]=1.[CH3:19][NH:20][NH2:21]>C1(C)C=CC=CC=1>[CH3:19][N:20]1[N:21]=[C:6]([C:5]2[CH:17]=[CH:18][C:2]([Br:1])=[CH:3][CH:4]=2)[C:8]2[C:9](=[CH:13][CH:14]=[CH:15][CH:16]=2)[C:10]1=[O:11]

Participants

4

Reactant 2

HCID 6061MethylhydrazineHCID 2560622-(4-Bromobenzoyl)benzoic acid

Product 1

HCID 8388214-(4-Bromophenyl)-2-methylphthalazin-1-oneYield 87%

Reagents, catalysts & solvents 1

HCID 1140TolueneSolvent

Procedure

To a suspension of 2-(4-bromobenzoyl)benzoic acid (15.0 g, 49.2 mmol) in toluene (75 mL) at room temperature was added methylhydrazine (2.88 mL, 54.1 mmol). The reaction mixture was heated to reflux while collecting water in a Dean Stark trap for 3 hours, additional methylhydrazine (2.0 mL) was added and refluxing was continued for 15 minutes. The reaction mixture was cooled to room temperature and the product was collected by filtration and dried in vacuo to afford 13.4 g (87%) of 2-methyl-4-(4-bromophenyl)-1-(2H)-phthalazinone, m.p. 168°-170° C.

Workup

  1. temperatureThe reaction mixture was heated
  2. temperatureto reflux
  3. customwhile collecting water in a Dean Stark trap for 3 hours
  4. additionadditional methylhydrazine (2.0 mL) was added
  5. temperaturerefluxing
  6. filtrationthe product was collected by filtration
  7. customdried in vacuo

Sources & evidence

ORD record
ord-c71224efa99e451d96777627c8179f4b
Source dataset
uspto-grants-1997_04
Patent number
US05624922

Reaction notes

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