反应详情

Diethyl azodicarboxylate (12.6 ml) was added to a solution of triphenylphosphine (20.8 g) in tetrahydrofuran (300 ml) at 0° C. After 15 minutes 3,4-dichlorophenol (12.9 g) was added, after a further 10 minutes tert-butyl 4-hydroxy-1--piperidinecarboxylate (14.5 g) in tetrahydrofuran (100 ml) was added dropwise over 0.5 hour. The solution was stirred at room temperature for 5 hours and concentrated to a small volume. The residue was partitioned between ether and brine. The organic phase was separated, dried and evaporated to a gum. Purification by chromatography (ethyl acetate:isohexane 95:5) gave the sub-titled product as an oil (20 g).

1. additionwas added dropwise over 0.5 hour
2. concentrationconcentrated to a small volume
3. customThe residue was partitioned between ether and brine
4. customThe organic phase was separated
5. customdried
6. customevaporated to a gum
7. customPurification by chromatography (ethyl acetate:isohexane 95:5)