1-Benzyl-(3R)-methylpiperazine-2-one → 1-Benzyl-3-methylpiperazine

HRID 1585145

Reaction equation

HRID 1585145 reaction equation
[CH2:1]([N:8]1[CH2:13][CH2:12][NH:11][C@H:10]([CH3:14])[C:9]1=O)[C:2]1[CH:7]=[CH:6][CH:5]=[CH:4][CH:3]=1.[H-].[Al+3].[Li+].[H-].[H-].[H-]>C1COCC1>[CH2:1]([N:8]1[CH2:13][CH2:12][NH:11][CH:10]([CH3:14])[CH2:9]1)[C:2]1[CH:3]=[CH:4][CH:5]=[CH:6][CH:7]=1

Participants

4

Reactant 2

HCID 100131621-Benzyl-(3R)-methylpiperazine-2-oneHCID 21226445Aluminium lithium hydride

Product 1

HCID 27275201-Benzyl-3-methylpiperazine

Reagents, catalysts & solvents 1

HCID 8028TetrahydrofuranSolvent

Procedure

A mixture of 1-benzyl-3R-methylpiperazine-2-one (XX, 4.36 g), lithium aluminum hydride (LAH, 2.33 g) and THF (125 ml) is heated at reflux for 16 hr. After cooling to 20-25°, the mixture is quenched slowly with water (2.3 ml), sodium hydroxide (10%, 3.5 ml) and water (5.7 ml). The residue is diluted with ether (100 ml) and is stirred for 1 hr. The solids are filtered and washed successively with ether, methylene chloride and ether. The combined filtrates are dried over potassium carbonate, filtered and concentrated to give 1-benzyl-(3R)-methylpiperazine (XXI), sufficiently pure to be carried on crude, NMR (CDCl3) 7.2-7.4, 3.49, 2.7-3.0, 1.95-2.1, 1.66, 1.3-1.7 and 1.01 δ.

Workup

  1. temperatureis heated
  2. temperatureat reflux for 16 hr
  3. temperatureAfter cooling to 20-25°
  4. customthe mixture is quenched slowly with water (2.3 ml), sodium hydroxide (10%, 3.5 ml) and water (5.7 ml)
  5. additionThe residue is diluted with ether (100 ml)
  6. filtrationThe solids are filtered
  7. washwashed successively with ether, methylene chloride and ether
  8. dry with materialThe combined filtrates are dried over potassium carbonate
  9. filtrationfiltered
  10. concentrationconcentrated

Sources & evidence

ORD record
ord-90b18e38d92f4710a1ffa98d5a8cfa15
Source dataset
uspto-grants-1999_08
Patent number
US05935970

Linked notes

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