反应详情

Analogously to the preparation of Example 1, 14.4 g (0.07 mol) of α-hydroxyimino-3,4-dimethoxybenzyl cyanide are reacted at room temperature with 26.56 g (0.077 mol) of 4-dodecylbenzenesulfonyl chloride in 100 ml of tetrahydrofuran in the presence of 10.6 g (0.105 mol) of triethylamine. For working-up, the reaction mixture is poured into water and extracted several times with methylene chloride. After drying over magnesium sulfate, the solvent is distilled off in a rotary evaporator. The brown oil that remains is then purified by flash chromatography on silica gel (eluant: petroleum ether/ethyl acetate 3:1). 14.75 g (41%) of α-(4-dodecylphenylsulfonyloxyimino)-3,4-dimethoxybenzyl cyanide are obtained in the form of a viscous yellow oil. The 1H-NMR spectrum shows that it is the (syn) isomer. The UV/Vis spectrum (acetonitrile) shows an absorption band at 350 nm (ε=10700) that extends to 435 nm. Elemental analysis: C28H38N2O5S

1. extractionextracted several times with methylene chloride
2. dry with materialAfter drying over magnesium sulfate
3. distillationthe solvent is distilled off in a rotary evaporator
4. customThe brown oil that remains is then purified by flash chromatography on silica gel (eluant: petroleum ether/ethyl acetate 3:1)