反应详情

温度

-60 °C

N6 -(2-(4-nitrophenyl)ethoxycarbonyl)-2'-deoxyadenosine (5 g, 11.3 mmol) was co-evaporated with pyridine (2×60 ml, pro analysi quality, additionally dried over molecular sieve 4 Å), dissolved in pyridine (60 ml, see above) and cooled to -60° C. (i-PrOH/N2). A solution of 2-(2-chloro-6-nitrophenyl)ethoxycarbonyl chloride (4.17 g, 15.8 mmol) in CH2Cl2 (60 ml, dist. over CaH2) was added dropwise for 2 h. After it had been stirred another 2 h in conditions of i-PrOH/N2 cooling (-40° to -25° C.), the mixture was diluted with CH2Cl2 (150 ml) and washed with H2O (100 ml). The aqueous phases were post-extracted with CH2Cl2 (100 ml). Drying the organic phases over Na2SO4, filtering, evaporating the solvent under reduced pressure and co-evaporating with toluene (3×50 ml) yielded the crude product (8.73 g) which was purified by column chromatography (400 g SiO2, 28×5.7 cm, solvent: CH2Cl2 /MeOH 100:3). 5'-O-(2-(2-chloro-6-nitrophenyl)ethoxycarbonyl)-N6 -(2-(4-nitrophenyl)ethoxycarbonyl)-2'-deoxyadenosine (6.318 g, 83%) was obtained as a colourless foam.

1. customadditionally dried over molecular sieve 4 Å),
2. dissolutiondissolved in pyridine (60 ml, see above)
3. washwashed with H2O (100 ml)
4. extractionThe aqueous phases were post-extracted with CH2Cl2 (100 ml)
5. dry with materialDrying the organic phases over Na2SO4
6. filtrationfiltering
7. customevaporating the solvent under reduced pressure and co-evaporating with toluene (3×50 ml)
8. customyielded the crude product (8.73 g) which
9. customwas purified by column chromatography (400 g SiO2, 28×5.7 cm, solvent: CH2Cl2 /MeOH 100:3)