反应详情

36 g of methyl 5-formylvalerate, 90 g of water and 0.5 g of sulfuric acid were refluxed for 3.5 hours, the methanol formed being distilled off constantly. Fractional distillation under reduced pressure gave 18.5 g (yield 57% of theory) of 5-formylvaleric acid of boiling point 106°-112° C./1 mbar. 13C NMR spectrum in D-chloroform: chemical shifts relative to tetramethyl silane as internal standard=21, 24, 34 and 44 ppm (4 methylene groups), 178 ppm (formyl group) and 203 ppm (carboxyl group).

1. distillationbeing distilled off constantly
2. distillationFractional distillation under reduced pressure