Reaktion #838840

Reaktionsgleichung

NaHCO3

p-toluene sulfonic acid hydrate

1-Boc-3-piperidone

ethylene glycol

→

desired product

1,4-Dioxa-7-aza-spiro [4.5] decane

Lösungsmittel

toluene

Reaktionsbedingungen

Aufarbeitung

1. 1
   Temperaturthe reaction heated
2. 2
   Temperaturto reflux
3. 3
   Sonstigefor 7 h
4. 4
   Sonstigethe organic layer was removed
5. 5
   SonstigeThe aqueous phase was evaporated to dryness
6. 6
   workup.DISSOLUTIONthe resulting residue dissolved in THF
7. 7
   FiltrationFiltration
8. 8
   Sonstigethrough celite and removal of the solvent in vacuo

Vorschrift

To a solution of 1-Boc-3-piperidone (700 mg, 3.51 mmol) in toluene (20 mL) was added ethylene glycol (588 μL, 10.54 mmol) followed by p-toluene sulfonic acid hydrate (1.0 g, 5.27 mmol) and the reaction heated to reflux using Dean-Stark apparatus for 7 h. To the mixture was added NaHCO3 solution, and the organic layer was removed. The aqueous phase was evaporated to dryness and the resulting residue dissolved in THF. Filtration through celite and removal of the solvent in vacuo gave the desired product as light brown oil. δH (CD3OD): 3.99 (2H, s), 3.73–3.57 (2H, m), 3.63 (4H, m), 2.77 (1H, m), 2.73 (1H, m), 1.76 (2H, m).

Quelle