1,4-Dibromobutane → Lesopitron

HRID 1735495Notes

Reaction equation

HRID 1735495 reaction equation
[N:1]1([C:7]2[N:12]=[CH:11][CH:10]=[CH:9][N:8]=2)[CH2:6][CH2:5][NH:4][CH2:3][CH2:2]1.Br[CH2:14][CH2:15][CH2:16][CH2:17]Br.C([O-])([O-])=O.[K+].[K+].[Cl:25][C:26]1[CH:27]=[N:28][NH:29][CH:30]=1>CN(C)C=O>[Cl:25][C:26]1[CH:27]=[N:28][N:29]([CH2:14][CH2:15][CH2:16][CH2:17][N:4]2[CH2:5][CH2:6][N:1]([C:7]3[N:8]=[CH:9][CH:10]=[CH:11][N:12]=3)[CH2:2][CH2:3]2)[CH:30]=1

Participants

6

Reactant 4

HCID 80561,4-DibromobutaneHCID 11430Potassium CarbonateHCID 275241H-Pyrazole, 4-chloro-HCID 887471-(2-Pyrimidinyl)piperazine

Product 1

HCID 60813Lesopitron

Reagents, catalysts & solvents 1

HCID 6228DimethylformamideSolvent

Procedure

To a mixture of 2- (1-piperazinyl)pyrimidine (32.8 g; 0.2 mol), 1,4-dibromobutane (47.5 g; 0.22 mol) and K2CO3 (69 g; 0.5 tool) in 400 ml of dimethylformamide is added 4 -chloropyrazole (20.5 g; 0.2 mol), and the mixture is held at the reflux for 17 hours. The reaction mixture is filtered hot and evaporated to dryness. The residue is dissolved in HCl, washed with CHCl3, rendered alkaline with dilute NaOH and extracted in basic medium with CHCl3. The organic phase is then dried and subsequently evaporated to dryness, and 61 g (95%) of 2-{4-[4-(4-chloro-1-pyrazolyl)butyl]-1-piperazinyl}pyrimidine are obtained.

Workup

  1. temperaturereflux for 17 hours
  2. filtrationThe reaction mixture is filtered hot
  3. customevaporated to dryness
  4. dissolutionThe residue is dissolved in HCl
  5. washwashed with CHCl3
  6. extractionextracted in basic medium with CHCl3
  7. customThe organic phase is then dried
  8. customsubsequently evaporated to dryness, and 61 g (95%) of 2-{4-[4-(4-chloro-1-pyrazolyl)butyl]-1-piperazinyl}pyrimidine
  9. customare obtained

Sources & evidence

ORD record
ord-a8049e01f1284a618ec5125c334fa334
Source dataset
uspto-grants-1996_07
Patent number
US05536836

Reaction notes

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