反応 #6365

反応方程式

diethyl azodicarboxylate

diethyl (R)-[2-benzyloxy-1-(hydroxymethyl)ethoxy]methylphosphonate

triphenylphosphine

2-[bis-(t-butoxycarbonyl)amino]-9-hydroxy-6-methoxypurine

→

(S)-2-[bis-(t-butoxycarbonyl)amino]-9-[3-benzyloxy-2-(diethoxyphosphorylmethoxy)propoxy]-6-methoxypurine

収率 88.6%

溶媒

THF

反応条件

後処理

1. 1
   workup.ADDITIONwas added
2. 2
   workup.WAITleft
3. 3
   その他The solvent was evaporated under reduced pressure
4. 4
   その他the residue obtained
5. 5
   その他chromatographed on silica gel

実験手順

To a stirred solution of diethyl (R)-[2-benzyloxy-1-(hydroxymethyl)ethoxy]methylphosphonate (1.0 g, 3 mmol), triphenylphosphine (1.18 g, 4.5 mmol) and 2-[bis-(t-butoxycarbonyl)amino]-9-hydroxy-6-methoxypurine (1.15 g, 3 mmol) in dry THF (20 ml), cooled in ice and under a mitrogen atmosphere, was added, dropwise, diethyl azodicarboxylate (0.71 ml, 4.5 mmol). The resulting solution was allowed to warm to ambient temperature and left stirring for 16 hours. The solvent was evaporated under reduced pressure and the residue obtained chromatographed on silica gel using hexane/ethyl acetate 2:1 as eluant. The eluant was changed as follows: hexane/ethyl acetate 1:1, hexane/ethyl acetate 1:2 and finally to ethyl acetate to give (S)-2-[bis-(t-butoxycarbonyl)amino]-9-[3-benzyloxy-2-(diethoxyphosphorylmethoxy)propoxy]-6-methoxypurine as a colourless oil (1.85 g, 88%).

出典