反应详情

温度

60 °C

Anhydride 1 (7.71 g; 50 mmol) was combined with triethyl orthoformate (12.5 mL; 75 mmol; 1.5 equiv) and ethanol (50 mL). p-Toluenesulfonic acid (0.48 g; 2.5 mmol; 0.05 equiv) was added and the reaction mixture was heated overnight at 60° C. to completely consume 1. Solid sodium bicarbonate (0.5 g) was added and the solvent was removed at reduced pressure. The residue was dissolved in toluene (25 mL), washed with saturated aqueous NaHCO3 (5 mL), dried over Na2SO4, and concentrated to afford 11.42 g (99%) of cis-2b which was a single peak by GC analysis.

1. customto completely consume 1
2. additionSolid sodium bicarbonate (0.5 g) was added
3. customthe solvent was removed at reduced pressure
4. dissolutionThe residue was dissolved in toluene (25 mL)
5. washwashed with saturated aqueous NaHCO3 (5 mL)
6. dry with materialdried over Na2SO4
7. concentrationconcentrated
8. customto afford 11.42 g (99%) of cis-2b which