反应 #417915

反应方程式

N2

9-(2-O-benzyl-β-D-arabinofuranosyl)-6-[2-(trimethylsilyl)ethoxy]-9H-purine

4,4′-dimethoxytrityl chloride

→

product

收率 44.4%

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

收率 44.4%

溶剂

EtOAc

hexane

triethylamine

EtOAc

hexane

pyridine

dichloromethane

反应条件

后处理

1. 1
   其他quenched with 100 mL saturated NaHCO3 solution
2. 2
   萃取After the aqueous layer was extracted with dichloromethane (100 mL) three times
3. 3
   其他evaporated
4. 4
   其他The residue was purified by flash chromatography (gradient

实验过程

Under the protection of N2, to a solution of 9-(2-O-benzyl-β-D-arabinofuranosyl)-6-[2-(trimethylsilyl)ethoxy]-9H-purine (1.60 g, 3.49 mmol) in 20 mL pyridine was added 4,4′-dimethoxytrityl chloride (2.13 g, 6.28 mmol). The mixture was stirred at room temperature for 2 h. The reaction was diluted with 100 mL dichloromethane and quenched with 100 mL saturated NaHCO3 solution. After the aqueous layer was extracted with dichloromethane (100 mL) three times, the organic layers were combined and evaporated. The residue was purified by flash chromatography (gradient: hexane with EtOAc 0-100%, with 1% triethylamine in both hexane and EtOAc) to produce 1.18 g (1.55 mmol, 44.4%) product. LCMS: for C43H48N4O7Si calculated 760.9. found 762.5 [M+H]+. 1H NMR (600 MHz, CD3CN) δ: 8.39 (s, 1H), 8.10 (s, 1H), 7.42-7.40 (m, 2H), 7.29-7.13 (m, 10H), 6.86-6.85 (m, 2H), 6.81-6.77 (m, 4H), 6.50 (d, J=5.5 Hz, 1H), 4.69-4.65 (m, 2H), 4.49-4.45 (m, 2H), 4.24-4.21 (m, 2H), 4.02 (m, 1H), 3.8 (dd, 10.4, 6.3 Hz, 1H), 3.29 (dd, J=10.4, 3.5 Hz, 1H), 1.22 (m, 2H), 0.09 (s, 1H). 13C NMR (600 MHz, CD3CN) δ: 160.82, 152.01, 142.44, 130.24, 130.21, 128.39, 128.25, 128.01, 127.86, 127.61, 127.05, 113.21, 83.56, 82.87, 82.37, 74.31, 72.54, 65.26, 63.56, 55.10, 17.27, −2.13.

来源