반응 #476546

반응 방정식

hydroxylamine

water

( 22 )

(3R,4R)-2,5-Dioxo-3,4-dibenzoyloxy-3,4-dihydrofuran

acetonitrile

→

title compound ( 23 )

수율 87.1%

1-Hydroxy-(3R,4R)-2,5-Dioxo-3,4-dibenzoyloxypyrrolidine

수율 87.1%

용매

toluene

반응 조건

후처리

1. 1
   기타To a 3-neck 5 L round bottom flask fitted with a mechanical stirrer
2. 2
   workup.DISSOLUTIONThe starting material gradually dissolved during the addition
3. 3
   온도the reaction mixture was warmed to 20° C.
4. 4
   농축The reaction mixture was concentrated in vacuo
5. 5
   workup.ADDITIONdiluted with EtOAc (1 L)
6. 6
   세척washed with 1 N HCl (2×1 L)
7. 7
   기타The organic phase was separated
8. 8
   농축concentrated in vacuo
9. 9
   기타to afford a viscous red syrup
10. 10
    workup.DISSOLUTIONThe syrup gradually dissolved
11. 11
    기타the product crystallized
12. 12
    온도After cooling to room temperature the solid
13. 13
    여과was collected by filtration
14. 14
    세척washed with 10% acetone in hexane (2×1 L)
15. 15
    기타dried in a vacuum oven

실험 절차

To a 3-neck 5 L round bottom flask fitted with a mechanical stirrer and a teflon coated temperature probe was added (22) (2.79 mol) followed by acetonitrile (2 L). The suspension was cooled in an ice bath to 4° C., followed by the addition of 50% aqueous hydroxylamine (180 mL, 2.93 mol) over 1 h. The starting material gradually dissolved during the addition and the reaction mixture was warmed to 20° C. and stirred for 1 h. The reaction mixture was concentrated in vacuo, diluted with EtOAc (1 L) and washed with 1 N HCl (2×1 L). The organic phase was separated and concentrated in vacuo to afford a viscous red syrup. The syrup was then heated for two hours in toluene (2.5 L) at 100° C. with azeotropic removal of water. The syrup gradually dissolved and then the product crystallized. After cooling to room temperature the solid was collected by filtration, washed with 10% acetone in hexane (2×1 L) and dried in a vacuum oven to afford the title compound (23) (862 g, 2.43 mol, 87%) as a white solid. 1H NMR (CDCl3, 400 MHz): δ 5.85 (s, 2H), 7.45 (app. t, 4H), 7.65 (app t, 2H), 8.05 (m, 4H).

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