Piperazine → 2-(Piperazin-1-yl)-1,3-benzoxazole

HRID 1780663Notes

Reaction equation

HRID 1780663 reaction equation
Cl[C:2]1[O:3][C:4]2[CH:10]=[CH:9][CH:8]=[CH:7][C:5]=2[N:6]=1.[NH:11]1[CH2:16][CH2:15][NH:14][CH2:13][CH2:12]1>ClCCl>[N:11]1([C:2]2[O:3][C:4]3[CH:10]=[CH:9][CH:8]=[CH:7][C:5]=3[N:6]=2)[CH2:16][CH2:15][NH:14][CH2:13][CH2:12]1

Participants

4

Reactant 2

HCID 4837PiperazineHCID 119862-Chlorobenzoxazole

Product 1

HCID 6478182-(Piperazin-1-yl)-1,3-benzoxazole

Reagents, catalysts & solvents 1

HCID 6344DichloromethaneSolvent2×

Procedure

A 3.07 g portion of 2-chlorobenzoxazole was dissolved in 10 ml of dichloromethane. Under cooling with ice, to this was added dropwise 3.45 g of anhydrous piperazine which has been dissolved in 30 ml of dichloromethane, followed by 1 hour of reaction. The reaction solution was concentrated under a reduced pressure, and the resulting residue was purified by a silica gel column chromatography (dichloromethane:methanol=20:1), followed by concentration of the eluate under a reduced pressure. Thereafter, the resulting residue was dissolved in 30 ml of water, neutralized with 1N hydrochloric acid, extracted with dichloromethane, washed with water, dehydrated with Na2SO4 and then concentrated under a reduced pressure to obtain 1.77 g of 2-(1-piperazinyl)benzoxazole.

Workup

  1. temperatureUnder cooling with ice
  2. customfollowed by 1 hour of reaction
  3. concentrationThe reaction solution was concentrated under a reduced pressure
  4. customthe resulting residue was purified by a silica gel column chromatography (dichloromethane:methanol=20:1)
  5. dissolutionThereafter, the resulting residue was dissolved in 30 ml of water
  6. extractionextracted with dichloromethane
  7. washwashed with water
  8. concentrationconcentrated under a reduced pressure

Sources & evidence

ORD record
ord-19959bd7970a4b4ca5bd69328cd003b3
Source dataset
uspto-grants-1997_05
Patent number
US05631257

Reaction notes

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