potassium hydroxide in ethanol T=20°C; Winget's condensation; 5 h;

1: aq. KOH / ethanol / 5 h / 20 °C 2: aq. HCl / methanol / Heating View Scheme

potassium hydroxide in ethanol T=20°C; Winget's condensation; 5 h;

1: potassium hydroxide / ethanol; water / 5 h / 0 - 20 °C 2: hydrogenchloride / methanol / 1 h / Reflux View Scheme

1: N-iodo-succinimide / N,N-dimethyl-formamide / 10 h / 70 °C / |Inert atmosphere 2: ethanol; water / 12 h / 0 - 20 °C / |Inert atmosphere 3: caesium carbonate; (1,1'-bis(diphenylphosphino)ferrocene)palladium(II) dichloride / N,N-dimethyl-formamide / 2 h / 70 °C / |Inert atmosphere; |Microwave irradiation 4: hydrogenchloride; methanol / water / 6 h / 0 - 50 °C / |Inert atmosphere View Scheme

1: 88 percent / KOH / ethanol / 15 h / Ambient temperature 2: 77 percent / H2O2, NaOH / methanol / 19 h / Ambient temperature 3: 76 percent / HCl / methanol / 0.25 h / 50 °C View Scheme

potassium hydroxide in ethanol T=20°C; Winget's condensation; 5 h;

potassium hydroxide in ethanol T=20°C; Winget's condensation; 5 h;

1: piperonal; ethanolic KOH-solution 2: acetic acid; aqueous sulfuric acid View Scheme