1: With tin(ll) chloride in ethanol 0.5 h; Reflux; 2: With sodium hydroxide in dichloromethane; water

1: sulfuric acid / |Reflux; |Molecular sieve 2: tin(ll) chloride / ethanol / 0.5 h / |Reflux View Scheme

1: 1,3-dibromo-5,5-dimethyl-hydantoin; sulfuric acid 2: sulfuric acid / |Reflux; |Molecular sieve 3: tin(ll) chloride / ethanol / 0.5 h / |Reflux View Scheme

acetic acid; sodium nitrite in water

1: acetic acid; sodium nitrite / water 2: sodium hydroxide; water / ethanol / 4 h / 20 °C View Scheme

1.1: acetic acid; sodium nitrite / water 2.1: sodium hydroxide; water / ethanol / 4 h / 20 °C 3.1: thionyl chloride / 1 h / |Reflux 3.2: 0 °C 4.1: potassium hydroxide; [bis(acetoxy)iodo]benzene / 3 h / 0 °C 5.1: water; potassium hydroxide / methanol / 48 h / |Reflux View Scheme

1: acetic acid; sodium nitrite / water 2: (1,1'-bis(diphenylphosphino)ferrocene)palladium(II) dichloride; potassium acetate / methanol / 16 h / |Inert atmosphere; |Reflux View Scheme