反应详情

温度

80 °C

5.7 g of 4-methoxy-3-pyrrolin-2-one and 10.8 g of benzyl alcohol were mixed with 0.4 g of methane sulfonic acid and stirred for 24 hours at 80° C. and 20 mbars. Then the reaction solution was mixed with 50 ml of ice water and 100 ml of methylene chloride and neutralized with 4 ml of saturated NaHCO3 solution. The aqueous phase was extracted twice more with 50 ml each of methylene chloride. After drying of the organic phase over Na2SO4 and distilling off of the solvent, the residue was mixed with 150 ml of ice water, heated to 100° C. and 100 ml of water-benzyl alcohol was azeotropically distilled off. The crystals precipitated during the cooling were recrystallized hot from 50 ml of toluene. 6.7 g of white, crystalline product with a melting point of 147° to 148° was obtained. For the product:

1. extractionThe aqueous phase was extracted twice more with 50 ml each of methylene chloride
2. dry with materialAfter drying of the organic phase over Na2SO4
3. distillationdistilling off of the solvent
4. additionthe residue was mixed with 150 ml of ice water
5. temperatureheated to 100° C.
6. distillation100 ml of water-benzyl alcohol was azeotropically distilled off
7. customThe crystals precipitated during the cooling
8. customwere recrystallized hot from 50 ml of toluene
9. custom6.7 g of white, crystalline product with a melting point of 147° to 148° was obtained