Hydrochloric Acid → (R)-1-Benzoyl-3-methylpiperazine

HRID 1514389Notes

Reaction equation

HRID 1514389 reaction equation
[CH3:1][C@@H:2]1[CH2:7][NH:6][CH2:5][CH2:4][NH:3]1.C(=O)(O)[O-].[Na+].[C:13](Cl)(=[O:20])[C:14]1[CH:19]=[CH:18][CH:17]=[CH:16][CH:15]=1.Cl>O.CC(C)=O>[CH3:1][C@H:2]1[NH:3][CH2:4][CH2:5][N:6]([C:13]([C:14]2[CH:19]=[CH:18][CH:17]=[CH:16][CH:15]=2)=[O:20])[CH2:7]1

Participants

7

Reactant 4

HCID 313Hydrochloric AcidHCID 7412Benzoyl chlorideHCID 516892Sodium BicarbonateHCID 73304342-Methylpiperazine, (R)-

Product 1

HCID 7578227(R)-1-Benzoyl-3-methylpiperazine

Reagents, catalysts & solvents 2

HCID 180AcetoneSolvent3×HCID 962WaterSolvent2×

Procedure

(R)-2-methylpiperazine (13.85 g, 138 mmol) and sodium bicarbonate (52.3 g, 622 mmol) were partially dissolved in a mixture of water (182 ml) and acetone (112 ml). A solution of benzoyl chloride (17.7 ml, 152 mmol) in acetone (56 ml) was added dropwise over 1 hour with vigorous stirring. After stirring for 16 hours at RT, the acetone was stripped on the rotovap, water (400 ml) was added, and the solution acidified (6M HCl) to a pH less than 2. The aqueous phase was washed three times with dichloromethane (200 ml) and then 5M sodium hydroxide was added to bring pH over 12. The resulting solution was extracted three times with dichloromethane (200 ml), dried (MgSO4) and evaporated to give (R)-(3-methylpiperazin-1-yl)(phenyl)methanone 62 as a yellow oil, 15.1 g (54% of theoretical). LC/MS m/z=205 (M+H+).

Workup

  1. additionwas added
  2. washThe aqueous phase was washed three times with dichloromethane (200 ml)
  3. addition5M sodium hydroxide was added
  4. extractionThe resulting solution was extracted three times with dichloromethane (200 ml)
  5. dry with materialdried (MgSO4)
  6. customevaporated

Sources & evidence

ORD record
ord-1e52bb2900e7472c901aa1aa41effa07
Source dataset
uspto-grants-2012_07
Patent number
US08222251B2

Reaction notes

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