| 摘要 |
PURPOSE:To prepare the titled compound useful as a preparation raw material of n-butanol, perfumery, etc., suppressing the polymerization reaction, at reduced energy cost, in high yield, by dehydrating an acetaldol compound using a cation exchange resin as the catalyst. CONSTITUTION:The objective compound can be prepared by feeding acetaldol or its derivative such as aldoxane, paraldol, etc. continuously to a cation exchange resin catalyst at a superficial velocity in column (SV) of 1-3l/hr, and carrying out the dehydration reaction at 90-120 deg.C under a pressure between atmospheric pressure and 10kg/cm<2>G. A strongly acidic cation exchange resin and a weakly acidic one can be used for the purpose. The acidity of the ion exchange resin is preferably selected according to the reaction conditions, because although a strongly acidic resin has higher catalytic activity under the same reaction condition, there is an upper limit in the tolerable temperature and it is necessary to compensate the temperature limitation by the amount of the catalyst, and on the other hand, although a weakly acidic ion exchange resin has lower rate of dehydration reaction, it has high tolerable temperature, and the aldol dehydration conversion can be increased to 100% by raising the reaction rate. |
