Reaktion #71417

Reaktionsgleichung

4-methoxybenzyl bromide

3,3-dimethyl-piperazin-2-one

4-methoxybenzyl bromide

triethylamine

→

title compound

Ausbeute 55.0%

4-(4-Methoxy-benzyl)-3,3-dimethyl-piperazin-2-one

Ausbeute 55.0%

Lösungsmittel

DCM

Reaktionsbedingungen

Aufarbeitung

1. 1
   workup.STIRRINGthe mixture was stirred for 72 h at rt
2. 2
   Einengenconcentrated
3. 3
   workup.ADDITIONThe residue was diluted with DCM/saturated aqueous solution of NaHCO3
4. 4
   SonstigeThe aqueous phase was separated
5. 5
   Extraktionextracted with DCM
6. 6
   WaschenThe organic phase was washed with H2O and brine
7. 7
   Trocknendried (Na2SO4)
8. 8
   Filtrationfiltered
9. 9
   Einengenconcentrated
10. 10
    SonstigeThe residue was triturated in DCM

Vorschrift

A mixture of 3,3-dimethyl-piperazin-2-one (Step 108.4) (3.7 g, 28.9 mmol), 4-methoxybenzyl bromide (5.4 mL, 37.6 mmol, 1.3 equiv) and triethylamine (5.2 mL, 37.6 mmol, 1.3 equiv) in DCM (60 mL) was stirred for 48 h at rt. Additional 5.0 mL of 4-methoxybenzyl bromide were added and the mixture was stirred for 72 h at rt, then concentrated. The residue was diluted with DCM/saturated aqueous solution of NaHCO3. The aqueous phase was separated and extracted with DCM. The organic phase was washed with H2O and brine, dried (Na2SO4), filtered and concentrated. The residue was triturated in DCM to provide 3.95 g of the title compound as a white solid: ESI-MS: 249.2 [M+H]+; TLC: Rf=0.16 (Hex/EtOAc, 2:3).

Quelle