Potassium Carbonate → 5-(1,3-Oxazol-2-yl)-1-azabicyclo[3.2.1]octane oxalate salt

HRID 654527

Reaction equation

HRID 654527 reaction equation
[N:1]12[CH2:8][C:5]([C:9]([NH2:11])=[O:10])([CH2:6][CH2:7]1)[CH2:4][CH2:3][CH2:2]2.[C:12]1(=O)[O:16][CH:15]=[CH:14][O:13]1.[C:18](=[O:21])([O-:20])[O-].[K+].[K+]>CCOCC>[C:12]([OH:16])(=[O:13])[C:18]([OH:20])=[O:21].[O:10]1[CH:15]=[CH:14][N:11]=[C:9]1[C:5]12[CH2:8][N:1]([CH2:7][CH2:6]1)[CH2:2][CH2:3][CH2:4]2

Participants

5

Reactant 3

HCID 11430Potassium CarbonateHCID 13385Vinylene carbonateHCID 198875881-Azabicyclo[3.2.1]octane-5-carboxamide

Product 1

HCID 198875785-(1,3-Oxazol-2-yl)-1-azabicyclo[3.2.1]octane oxalate saltYield 16%

Reagents, catalysts & solvents 1

HCID 3283Diethyl EtherSolvent

Procedure

A stirred mixture of 1-azabicyclo[3.2.1]oct-5-ylcarboxamide (D20, 1.50 g, 0.0097 mole) and vinylene carbonate (1.2 g, 0.014 mole) in polyphosphoric acid (35 g) was heated at 120°-130° C. for 2h. The reaction mixture was allowed to cool, then treated with ice, before basifying with potassium carbonate solution. The aqueous was shaken well with ether, then the mixture filtered and the organic layer separated. The aqueous was again extracted with ether (2×80 ml) and all the ether extracts combined, dried (Na2SO4) and concentrated in vacuo to leave a yellow oil. This was chromatographed on a basic alumina column eluting with ethyl acetate and the material obtained converted to its oxalate salt and recrystallised from methanol/ether to give the title compound (E12) as a white solid (410 mg, 16%) m.p. 143°-145° C.

Workup

  1. temperaturewas heated at 120°-130° C. for 2h
  2. temperatureto cool
  3. additiontreated with ice
  4. filtrationthe mixture filtered
  5. customthe organic layer separated
  6. extractionThe aqueous was again extracted with ether (2×80 ml) and all the ether
  7. dry with materialdried (Na2SO4)
  8. concentrationconcentrated in vacuo
  9. customto leave a yellow oil
  10. customThis was chromatographed on a basic alumina column
  11. washeluting with ethyl acetate
  12. customthe material obtained
  13. customrecrystallised from methanol/ether

Sources & evidence

ORD record
ord-e74371503dec42b8bb8460ca93b88ad0
Source dataset
uspto-grants-1992_07
Patent number
US05132316

Linked notes

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