反应详情

4.33 g of (S)-2,2,4-trimethyl-1,3-dioxolan-4-ethanol dissolved in 7 ml of absolute methylene chloride were added dropwise to a suspension of 7.59 g of pyridine chlorochromate in 30 ml of absolute methylene chloride. The reaction mixture was stirred at room temperature for 3 hours. By addition of 75 ml of ether, the chromium salt was precipitated and separated by filtration over 120 g of Kieselgel. After removal of the solvent on a rotary evaporator and distillation of the residue at 90°-100°/10 mmHg, there were obtained 3.00 g of (S)-2,2,4-trimethyl-1,3-dioxolan-4-acetaldehyde. [α]D20 =-35.5° (c=1.50; n-hexane).

1. customthe chromium salt was precipitated
2. customseparated by filtration over 120 g of Kieselgel
3. customAfter removal of the solvent
4. customon a rotary evaporator and distillation of the residue at 90°-100°/10 mmHg