Reaktion #51872

Reaktionsgleichung

2-ureidoacetate

hydroxylamine

→

N-hydroxy-2-ureidoacetamide

Lösungsmittel

dioxane

Reaktionsbedingungen

Aufarbeitung

1. 1
   FiltrationThe resin was filtered
2. 2
   Waschenwashed with acetonitrile
3. 3
   Sonstigepurified by preparative reverse-phase (C18) HPLC

Vorschrift

A stock solution of triphosgene was prepared from solid triphosgene (1.48 g, 5 mmol) and DCM (20 mL). The solution was cooled to −78° C. and triethylamine (2 mL, 15 mmol) was slowly added. To ArgoGel-Wang or ArgoGel-OH resin bound 2-aminoacetate 4 (0.5 g) was added the triphosgene solution (3.5 mL) and the resin was shaken at rt for 1 h. The resin was drained, washed with DCM (3×) and then suspended in a solution of secondary amine 7 (e.g., pyrrolidine, 2 mmol) and TEA (3 mmol) in DCM (2 mL). After 16 h, the resin was washed with DCM and MeOH (3× each) to yield ArgoGel-Wang or ArgoGel-OH resin bound 2-ureidoacetate 6 which was then treated with a solution of aqueous 50% hydroxylamine (2 mL) and dioxane (1 mL) for 2 days. The resin was filtered, washed with acetonitrile and the filtrates combined and purified by preparative reverse-phase (C18) HPLC to yield product N-hydroxy-2-ureidoacetamide (I).

Quelle