US Patent 7803971 Method for the production of cyclopentanone

A process for preparing cyclopentanone, at least comprising the following steps (i) to (iii):(i) providing a mixture G(i) comprising cyclopentene;(ii) providing liquid or supercritical N2O or a liquid or supercritical gas mixture G(ii) comprising at least 20% by volume of N2O, based on the total volume of the mixture G(ii);(iii) contacting the mixture G(i) with the liquid or supercritical N2O or the liquid or supercritical mixture G(ii) to obtain a mixture G(iii) comprising cyclopentanone,wherein the mixture G(i) contains at least 25% by weight and at most 95% by weight, of cyclopentene, based on the total weight of the mixture G(i).