| 摘要 |
PURPOSE:To obtain acyclic or cyclic chloroacetals in high purity independent of production of raw materials by reacting a monochloracetoaldehyde trimer with a 1-5C mono- or dihydric alcohol in the presence of an acid catalyst or a dehydrating agent. CONSTITUTION:A monochloroacetaldehyde(MCA) monomer is reacted with a 1-5C mono- or dihydric alcohol in the presence of an acid catalyst, e.g. p- toluenesulfonic acid or dilute sulfuric acid or a dehydrating agent such as anhydrous calcium chloride at >=120 deg.C, preferably 130-160 deg.C temperature under ordinary or higher pressure. Thereby, MCA trimer capable of stably existing for a long period is used as a raw material for acetalization to industrially and advantageously provide acyclic or cyclic chloroacetals useful as a raw material for medicines or polymer compounds in high purity. Furthermore, the MCA trimer may be heated in the presence of the acid catalyst to afford a monomer, which is then reacted with the aforementioned alcohol. |
