摘要 |
Laurolactam is prepared by: (a) reacting cyclododecatriene with carbon monoxide and hydrogen in the presence of a catalyst mixture consisting of (i) an oxonation catalyst and (ii) a hydrogenation catalyst which is not poisoned by carbon monoxide, to form a mixture of hydroxymethylcyclododecane and bis-(cyclododecylmethyl) ether; (b) dehydrogenating this mixture in an alkali melt to form cyclododecane carboxylic acid; and (c) nitrosating this by a conventional method with a mixture of nitrosylsulphuric acid and oleum and rearranging the product into laurolactam. In modifications, the mixture from step (a) is separated into its components, e.g. by distillation, and only the hydroxymethylcyclododecane is subjected to step (b). The resulting cyclododecane carboxylic acid is then subjected to step (c) alone or with the ether product separated after step (a). Catalyst (i) preferably comprises a Co compound, a Pd compound or finely divided Pd. Suitable catalysts (ii) include those containing Cu (II) oxide and chromium oxide; Pt or Ag/Zn/Cr oxides.ALSO:A catalyst mixture comprising dicobalt octacarbonyl and a hydrogenation catalyst prepared by mixing aqueous solutions of Cu (NO3)2, Na2Cr2O7 and NH3, filtering, washing and drying at 320-330 DEG C, is used to prepare a mixture of hydroxymethyl-cyclododecane and bis(cyclododecylmethyl) ether by reacting cyclododecatriene with CO and H2. |