Reaktion #71512

Reaktionsgleichung

5-iodocytidine

bicarbonate

propargyltrifluoroacetamide

triethylamine

→

5-[3-(trifluoroacetamido)propynyl]cytidine

Ausbeute 67.0%

Lösungsmittel

DMF

methanol dichloromethane

Reaktionsbedingungen

Aufarbeitung

1. 1
   workup.ADDITIONwere added to the reaction mixture under N2
2. 2
   workup.STIRRINGAfter stirring for about one h
3. 3
   Filtrationthe reaction mixture was filtered
4. 4
   Waschenthe resin was washed with 1:1 methanol-dichloromethane
5. 5
   EinengenThe combined filtrates were rapidly concentrated with a rotary evaporator
6. 6
   SonstigeThe residue was immediately purified by flash chromatography
7. 7
   SonstigeRemoval of solvent from the appropriate fractions

Vorschrift

A 100-mL three-necked flask was charged with 5-iodocytidine (2.66 g, 7.00 mmol, 1.00 equiv.), cuprous iodide (0.267 g, 1.40 mmol, 0.20 equiv.) and dry DMF (35 mL). After complete dissolution of the reaction mixture, propargyltrifluoroacetamide (3.17 g, 21.00 mmol, 3.00 equiv.), triethylamine (1.42 g, 14.00 mmol, 2.00 equiv.) and finally tetrakis(triphenylphosphine)palladium(0) (0.809 g, 0.70 mmol, 0.10 equiv.) were added to the reaction mixture under N2. The reaction was stirred at ambient temperature (around 19° C. to around 22° C.) under N2 for 18-24 h. The reaction was then diluted with 70 mL of 1:1 methanol-dichloromethane and the bicarbonate form of AGI X8 resin (12.00 g) was added. After stirring for about one h, the reaction mixture was filtered and the resin was washed with 1:1 methanol-dichloromethane. The combined filtrates were rapidly concentrated with a rotary evaporator. The residue was immediately purified by flash chromatography. Removal of solvent from the appropriate fractions afforded 1.84 g (67%) of 5-[3-(trifluoroacetamido)propynyl]cytidine as a light brown solid, which was confirmed by 1H-NMR.

Quelle