反応 #741709

反応方程式

1-azabicyclo[3.2.1]oct-5-ylcarboxamide

vinylene carbonate

potassium carbonate

→

title compound

収率 16.0%

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

収率 16.0%

溶媒

—

polyphosphoric acid

ether

反応条件

後処理

1. 1
   温度was heated at 120°-130° C. for 2h
2. 2
   温度to cool
3. 3
   workup.ADDITIONtreated with ice
4. 4
   ろ過the mixture filtered
5. 5
   その他the organic layer separated
6. 6
   抽出The aqueous was again extracted with ether (2×80 ml) and all the ether
7. 7
   乾燥dried (Na2SO4)
8. 8
   濃縮concentrated in vacuo
9. 9
   その他to leave a yellow oil
10. 10
    その他This was chromatographed on a basic alumina column
11. 11
    洗浄eluting with ethyl acetate
12. 12
    その他the material obtained
13. 13
    その他recrystallised from methanol/ether

実験手順

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.

出典