Reacción #417916

Ecuación de reacción

N2

2-cyanoethyl-N,N-diisopropylchlorophosphoramidite

9-{5-O-[bis(4-methoxyphenyl)(phenyl)methyl]-2-O-benzyl-β-D-arabinofuranosyl}-6-[2-(trimethylsilyl)ethoxy]-9H-purine

N,N-diisopropylethylamine

1-methylimidazole

→

final product

Rendimiento 94.8%

9-{5-O-[bis(4-methoxyphenyl)(phenyl)methyl]-3-O-[(2-cyanoethoxy) (dipropan-2-ylamino)phosphanyl]-2-O-benzyl-β-D-arabinofuranosyl}-6-[2-(trimethylsilyl)ethoxy]-9H-purine

Rendimiento 94.8%

Disolventes

EtOAc

hexane

triethylamine

EtOAc

hexane

tetrahydrofuran

Condiciones de reacción

Tratamiento posterior

1. 1
   OtroThe reaction was then quenched with methanol (5 mL)
2. 2
   workup.STIRRINGstirred for 5 min
3. 3
   OtroAfter the solvent was removed under the reduced pressure
4. 4
   Otrothe residue was purified by flash chromatography (gradient

Procedimiento

Under the protection of N2, 2-cyanoethyl-N,N-diisopropylchlorophosphoramidite (0.69 mL, 3.10 mmol) was added drop-wise to a 0° C. anhydrous tetrahydrofuran (12 mL) solution of 9-{5-O-[bis(4-methoxyphenyl)(phenyl)methyl]-2-O-benzyl-β-D-arabinofuranosyl}-6-[2-(trimethylsilyl)ethoxy]-9H-purine (1.18 g g, 1.55 mmol), N,N-diisopropylethylamine (0.81 mL, 4.65 mmol)), and 1-methylimidazole (0.06 mL, 0.78 mmol). The reaction was gradually warmed to room temperature and stirred for 60 min. The reaction was then quenched with methanol (5 mL) and stirred for 5 min. After the solvent was removed under the reduced pressure, the residue was purified by flash chromatography (gradient: hexane with EtOAc 0-50%, with 1% triethylamine in both hexane and EtOAc) to produce 1.41 g (94.6%, 1.47 mmol) final product. LCMS: for C52H65N6O5PSi calculated 961.167. found 961.6 [M+H]+. 31P NMR (600 MHz, CD3CN) δ: 150.65, 150.24.

Fuente