Trimethylsilylacetylene → 2',3'-bis-O-(tert-butyldimethylsilyl)-5'-deoxy-5-[(trimethylsilyl)ethynyl]-N4-(n-pentyloxycarbonyl)-cytidine

Participants

Reaction Steps

To a solution of 2′,3′-bis-O-(tert-butyldimethylsilyl)-5′-deoxy-5-iodo-N4-(n-pentyloxycarbonyl)cytidine (130 mg, 0.18 mmol) in CH2Cl2(2 ml) and Et3N(2 ml) Cul (10.7 mg, 0.1056 mmol), Pd(PPh3)2Cl2 (2.6 mg, 0.0036 mmol), and trimethylsilyl-acetylene (58.6 μl, 0.40 mmol) were added and stirred for 2 hours at room temperature under Ar in the dark. The reaction mixture was concentrated under reduced pressure and the residue was dissolved in EtOAc(25 ml×3), washed with 2% aq. EDTA·2Na(10 ml×2), water and brine, dried over Na2SO4 and filtered. The filtrate was evaporated under reduced pressure. The crude product was purified by flash chromatography on SiO2 (eluent: 10% EtOAc/n-hexane) to give 2′,3′-bis-O-(tert-butyldimethylsilyl)-5′-deoxy-5-[(trimethylsilyl)ethynyl]-N4-(n-pentyloxycarbonyl)-cytidine as a colorless amorphous solid. (30.2 mg, 26% yield).

Provenance & Evidence