反应详情

To a solution of 1,4-dibenzyl-2-(hydroxymethyl)piperazine (1.51 g), phthalimide (0.790 g) and triphenylphosphine (1.40 g) in tetrahydrofuran (20 ml) was added a 40% toluene solution (2.34 ml) of diethyl azodicarboxylate under ice cooling. The resulting mixture was stirred at room temperature for 6 hours. Furthermore, 1,4-dibenzyl-2-(hydroxymethyl)piperazine (0.87 g), phthalimide (0.486 g), triphenylphosphine (0.81 g) and tetrahydrofuran (5 ml) were added to the reaction mixture, followed by the addition of a 40% toluene solution (1.34 ml) of diethyl azodicarboxylate under ice cooling. The resulting mixture was stirred at room temperature for 18.5 hours. Phthalimide (0.405 g) and a 40% toluene solution (1.10 ml) of diethyl azodicarboxylate were added under ice cooling, followed by stirring at room temperature for 20 hours. The solvent was distilled off under reduced pressure. The residue was subjected to column chromatography twice (3% methanol—methylene chloride for the first time and ethyl acetate/hexane=1/3 for the second time) using as a carrier silica gel, whereby a crude product was obtained. The crude product was crystallized from hexane - methylene chloride, collected by filtration and washed with hexane, whereby the title compound (0.243 g) was obtained as colorless powder.

1. stirringThe resulting mixture was stirred at room temperature for 18.5 hours
2. stirringby stirring at room temperature for 20 hours
3. distillationThe solvent was distilled off under reduced pressure
4. customwas obtained
5. customThe crude product was crystallized from hexane - methylene chloride
6. filtrationcollected by filtration
7. washwashed with hexane, whereby the title compound (0.243 g)
8. customwas obtained as colorless powder