反应详情

Step E To a suspension of (S)-5-(tert-butyl-dimethyl-silanyloxy)-2-methyl-pentane-2,3-diol (6.8 g, 27 mmol) in 2,2-dimethoxypropane (35 mL) was added p-toluenesulfonic acid monohydrate (0.2 g). The reaction mixture was stirred at room temperature for 30 min. The mixture was partitioned between water and dichloromethane. The organic layer was separated, the aqueous layer was extracted with dichloromethane. The organic layers were combined, washed with water, brine, dried over MgSO4, and concentrated. The residue was purified by chromatography (EtOAc:hexanes=1:20) to give tert-butyl-dimethyl-[2-((S)-2,2,5,5-tetramethyl-[1,3]dioxolan-4-yl)-ethoxy]-silane as a yellow oil (4.56 g, 58%).

1. customThe mixture was partitioned between water and dichloromethane
2. customThe organic layer was separated
3. extractionthe aqueous layer was extracted with dichloromethane
4. washwashed with water, brine
5. dry with materialdried over MgSO4
6. concentrationconcentrated
7. customThe residue was purified by chromatography (EtOAc:hexanes=1:20)