Process for preparing cyclododecanone

A process for the purification of cyclododecane (CDAN) comprising the consecutive steps of:

• a) reaction of 1,5,9-cyclododecatriene (CDT) to afford a mixture of cyclododecanol (CDOL) and CDON,
• b) dehydrogenation of the CDOL to afford CDON, wherein a CDON-containing mixture which comprises cyclododecane (CDAN) is obtained,
• c) distillation of the CDON-containing mixture to obtain a fraction comprising CDAN (CDAN-containing fraction) and a CDON-containing fraction, and
• d) crystallizing-out CDAN from the CDAN-containing fraction by melt crystallization or solution crystallization;
• and
• wherein the mixture of CDOL and CDON is obtained by the consecutive steps of
• i) hydrogenation of CDT to afford CDAN and
• ii) oxidation of CDAN to afford the mixture of CDOL and CDON;
• or
• wherein the mixture of CDOL and CDON is obtained by the consecutive steps of
• I) hydrogenation of CDT to afford cyclododecene (CDEN),
• II) epoxidation of CDEN to afford cyclododecane epoxide (CDAN epoxide) and
• III) rearrangement of CDAN epoxide to afford the mixture of CDOL and CDON.