Reaktion #3745

Reaktionsgleichung

thymidine

imidazole

tert-butyldimethyl silyl chloride

→

5'-O-(tert-butyldimethylsilyl) thymidine

Ausbeute 70.1%

Lösungsmittel

DMF

Reaktionsbedingungen

Aufarbeitung

1. 1
   SonstigeDMF was then removed in vacuo
2. 2
   workup.DISSOLUTIONthe residue was dissolved in 150 ml of ethyl acetate
3. 3
   WaschenThe solution was washed with water
4. 4
   Trocknenthe organic layer was dried over MgSO4
5. 5
   SonstigeAfter removing the solvent
6. 6
   Sonstigethe solid was recrystallized with ethyl acetate/pentane

Vorschrift

To a solution of 2.42 g (10 mmol) thymidine in 15 ml DMF was added 1.7 g (25 mmol) imidazole and 1.6 g (10.6 mmol) tert-butyldimethyl silyl chloride. The solution was stirred at room temperature for 3 hours. DMF was then removed in vacuo and the residue was dissolved in 150 ml of ethyl acetate. The solution was washed with water and the organic layer was dried over MgSO4. After removing the solvent, the solid was recrystallized with ethyl acetate/pentane to obtain 2.5 g pure 5'-O-(tert-butyldimethylsilyl) thymidine 1 (70% yield).: m.p. 193°-194° C.; 1H NMR (500 MHz, CDCl3) δ9.0 (s, 1H, NH), 7.50 (s, 1H, H-6), 6.36 (dd, J=5.8, 8.1 Hz, 1H, H-1'), 4.44 (m, 1H, H-3'), 4.03 (m, 1H, H-4'), 3.85 (m, 2H, H-5'), 2.66 (d, J=3.8 Hz, 1H, OH), 2.35 (m, 1H, H-2'), 2.07 (m, 1H, H-2'), 1.89 (s, 3H, C=CMe), 0.89 (s, 9H, CMe3), 0.09 (s, 6H, SiMe2); --NMR (125 MHz, CDCl3) δ163.8 (C-4), 150.4 (C-2), 135.4 (C-6), 110.9 (C-5), 87.2 (C-4'), 85.0 (C-1'), 72.6 (C-3'), 63.6 (C-5'), 41.1 (C-2'), 25.9 (SiCMe3), 18.3 (SiCMe3), 12.5 (C=CMe), -5.4 (SiMe2), -5.5 (SiMe2).

Quelle