Reaktion #71631

Reaktionsgleichung

NaHCO3

4-bromobenzaldehyde

1,1-dimethylethyl (2R,6S)-2,6-dimethyl-1-piperazinecarboxylate

sodium triacetoxyborohydride

→

title compound

Ausbeute 91.8%

1,1-Dimethylethyl (2R,6S)-4-[(4-bromophenyl)methyl]-2,6-dimethyl-1-piperazinecarboxylate

Ausbeute 91.8%

Lösungsmittel

1,2-DCE

Reaktionsbedingungen

Aufarbeitung

1. 1
   workup.STIRRINGthe mixture stirred for 30 mins
2. 2
   ExtraktionThe product was extracted into EtOAc
3. 3
   Trocknenthe extracts dried (Na2SO4)
4. 4
   Einengenconcentrated
5. 5
   workup.DISSOLUTIONThe residue was dissolved in DCM
6. 6
   workup.ADDITIONtreated with PS-hydrazine resin
7. 7
   workup.STIRRINGwith stirring for 2 h
8. 8
   SonstigeThe resin was removed by filtration
9. 9
   Sonstigethe solvent removed in vacuo

Vorschrift

A mixture of 4-bromobenzaldehyde (1.85 g, 10 mmol), 1,1-dimethylethyl (2R,6S)-2,6-dimethyl-1-piperazinecarboxylate (2.15 g, 10 mmol) and sodium triacetoxyborohydride (3.18 g) in 1,2-DCE (35 ml) was stirred at room temperature for 3 days. Saturated aq. NaHCO3 solution was added and the mixture stirred for 30 mins. The product was extracted into EtOAc and the extracts dried (Na2SO4) and concentrated. The residue was dissolved in DCM and treated with PS-hydrazine resin with stirring for 2 h. The resin was removed by filtration and the solvent removed in vacuo. Chromatography (0-40% EtOAc/hexane) gave the title compound (3.52 g). MS (ES): MH+ 383/385.

Quelle