反应详情

To a solution of methyl 5-chloro-2-hydroxybenzoate (2.07 g, 11 mmol) and diisopropyl azodicarboxylate (2.98 g, 14 mmol) (Aldrich) in anhydrous tetrahydrofuran (10 mL) at 0° C. was added a mixture of trans-4-(tert-buyl-dimethyl-silanyloxy)-cyclohexanol (3.2 g, 14 mmol) and triphenylphosphine (3.64 g, 14 mmol) in tetrahydrofuran (40 mL). The reaction mixture was stirred at room temperature for 18 h. The mixture was poured into water, extracted with ethyl acetate (3×). The organic layers were combined, washed with water, brine, dried over MgSO4, and concentrated. The residue was purified by chromatography (5% EtOAc;hexanes) to give cis-2-[4-(tert-butyl-dimethyl-silanyloxy)-cyclohexyloxy]-5-chloro-benzoic acid methyl ester as a yellow oil (Yield 4.0 g, 90%).

1. extractionextracted with ethyl acetate (3×)
2. washwashed with water, brine
3. dry with materialdried over MgSO4
4. concentrationconcentrated
5. customThe residue was purified by chromatography (5% EtOAc;hexanes)