Reaktion #353425

Reaktionsgleichung

water

2-amino-6-methoxyethoxy purine

lithium hydride

3-(diethylphosphonomethoxy)-1-bromopropane

→

2-amino-9-(3-(diethylphosphonomethoxy)propyl]-6-methoxyethoxy purine

Lösungsmittel

dimethylformamide

DMF

Reaktionsbedingungen

Aufarbeitung

1. 1
   Sonstigeprepared
2. 2
   Temperaturthe solution was heated at 55° C. for 4 h
3. 3
   TemperaturThe reaction mixture was then cooled to room temperature
4. 4
   SonstigeInsoluble material was removed by filtration
5. 5
   EinengenThe filtrate was concentrated in vacuo
6. 6
   Sonstigeto give a viscous oil which
7. 7
   Sonstigewas purified by column chromatography on silica gel (5% methanol in CH2Cl2)

Vorschrift

To a suspension of lithium hydride (560 mg, 60 mmol) in dry dimethylformamide (DMF, 200 ml) was added 2-amino-6-methoxyethoxy purine (8.0 g, 40 mmol) (prepared according to the literature procedure: J. Kjellberg, M. Liljenberg and N. G. Johansson, Tetrahedron Lett. 877, 1986]and stirred for 60 min at 25° C. To this solution was added over 3 min a solution of 3-(diethylphosphonomethoxy)-1-bromopropane (12.0 g, 41.5 mmol) in DMF (5 mL) and the solution was heated at 55° C. for 4 h. The reaction mixture was then cooled to room temperature and water (50 mL) was added dropwise. Insoluble material was removed by filtration. The filtrate was concentrated in vacuo to give a viscous oil which was purified by column chromatography on silica gel (5% methanol in CH2Cl2) to afford 2-amino-9-(3-(diethylphosphonomethoxy)propyl]-6-methoxyethoxy purine as a white crystalline solid: yield 3.45 g (21%); mp 78°-79° C.

Quelle