| 摘要 |
PURPOSE:To obtain the subject compound which is useful as an intermediate of medicines or agricultural chemicals, especially prostaglandin safely in high yield with industrial advantage by dehydrohalogenation of a specific alcohol with a base in a solvent. CONSTITUTION:The reaction of 2-hexenone with 2,3-dihalogeno-1-propene of formula I (X is halogen, Y is Cl, Br) is carried out in a solvent such as tetrahydrofuran in the presence of Zn powder or fine dust and water, when needed, in the coexistence of ammonium halide to give an alcohol of formula II. Then, the alcohol is allowed to react with a base such as caustic soda in an amount of usually 1 to 15 equivalents in a solvent such as dimethylformamide at -20 to 120 deg.C until the alcohol disappears. After completion of the dehydrohalogenation, the reaction mixture is filtered, combined with water poured, extracted, separated and the organic phase is concentrated to give the subject compound. |
