| 摘要 |
<p>o -Laurolactam is prepared by reacting cyclododecanone with aqueous hydroxylamine until a mixed product of cyclododecanone and cyclododecanone oxime is obtained, separating said mixture and reacting it with HCl in the presence of a polar organic solvent to give a mixture of cyclododecanone and o -laurolactam, recovering the lactam, and recycling the cyclododecanone to the first reaction zone. Reaction with hydroxylamine is preferably at a pH of 4 to 7 and the product may contain 10-50% by weight of cyclododecanone; preferably 1/4 to 3/4 mole of hydroxylamine is used per mole of ketone. The mixture of ketone and oxime may be separated from the reaction mixture by filtration or extraction. Suitable polar solvents for the rearrangement to lactam include nitrocarbons, halocarbons and nitriles. A catalyst may be used, e.g. phosgene, 1,3,5-trichloro-S-triazine, 2,4-dibromo-pyrimidine, a 2-chloroazacycloalkene or a 2,2-dichloroazaalkane.</p> |
