PURPOSE: To obtain the subject compounds of high quality in a high yield by Beckmann's rearrangement reaction of cyclohexanone oxime and cyclododecanone oxime in a specified condition.
CONSTITUTION: Cyclohexanone oxime is blended with cyclododecanone oxime in a weight ratio of (40/60)-(70/30) and then subjected to continuous Beckmann's rearrangement reaction in the presence of sulfuric acid and fuming sulfuric acid. In this reaction, the quantity of fuming sulfuric acid used is controlled so that the concentration of free SO3 in the rearrangement reaction solution and the molar ratio (m) of sulfuric acid to oximes may satisfy 0.5wt.% ≤free SO3 concentration ≤4wt.% and 1.2<(molar number of sulfuric acid + molar number of free SO3)/(molar number of OX-6 + molar number of OX-12) = m≤1.75 (OX-6 is cyclohexanone oxime; OX-12 is cyclododecanone oxime) and the reaction is carried out at 85-100°C for 1-3hr. The resultant rearrangement reaction solution is then preferably subjected to heat treatment, thus obtaining the objective compounds.
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KUROKAWA YASUHIRO
NAWATA YOSHIHIRO
KAWAI JOJI
