反应详情

To a stirring solution of methyl 4-tert-butyl-2-hydroxybenzoate (9.45 g, 45.4 mmol), 1-Boc-piperidine-4-ol (9.6 g, 47.7 mmol) and triphenylphosphine (12.5 g, 47.7 mmol) in THF (125 mL) was added, dropwise via an addition funnel, a solution of diisopropyl azodicarboxylate (9.4 mL, 47.7 mmol) in THF (25 mL). After 72 h, the solvent was removed in vacuo and the residue was dissolved in a minimal amount of chloroform and vacuum filtered through a pad of silica gel, eluting with a solution of 20% ethyl acetate in hexanes. The filtrate was then concentrated in vacuo and the residue was chromatographed over silica gel, eluting with a gradient of 5% ethyl acetate in hexanes through 20% ethyl acetate in hexanes. The product containing fractions were combined and concentrated in vacuo to give 12.9 g (73% of a thick colorless oil).

1. customthe solvent was removed in vacuo
2. dissolutionthe residue was dissolved in a minimal amount of chloroform and vacuum
3. filtrationfiltered through a pad of silica gel
4. washeluting with a solution of 20% ethyl acetate in hexanes
5. concentrationThe filtrate was then concentrated in vacuo
6. customthe residue was chromatographed over silica gel
7. washeluting with a gradient of 5% ethyl acetate in hexanes through 20% ethyl acetate in hexanes
8. additionThe product containing fractions
9. concentrationconcentrated in vacuo