Chemoselective hydrogenation of phenol to cyclohexanol using heterogenized cobalt oxide catalysts

Cyclohexanol is an important intermediate in the synthesis of Nylon-6 and plasticizers. In this work, cobalt oxide nanoparticles (NPs) supported on porous carbon (CoO_x@CN) were fabricated by one-pot method and the hybrids could efficiently and selectively hydrogenate phenol to cyclohexanol with a high yield of 98%. The high catalytic performance of CoO_x@CN was associate with the high surface area (340 m²/g) and uniformly dispersed NPs. Furthurmore, by detailed analysing the relationship between catalytic activity and catalysts composition, it clearly indicated that the Co₃O₄ in CoO_x@CN played an important role for the adsorption and activation of phenol and the in situ gernerated Co was responsible for hydrogen adsorption and dissociation. These findings provide a fundamental insight into the real active sites in hydrogenation of phenol using Co-based catalysts.