Use of a catalyst system and oxidation oxidation process which uses this system.

A substrate (eg, a cycloalkane, a polycyclic hydrocarbon, an aromatic compound with a methyl group or METHYLENE ADJACENT TO CYCLING AROMATICO) is oxidized with oxygen in the presence of an oxidation catalyst comprising an imide compound represented by the following formula (1) (eg N hydroxyphthalimide) and a cocatalyst (EXCLUDING ACID FOSFOVANADOMOLIBDICO) containing an element selected from the group consisting of elements of Group 2A of the Periodic Table of the Elements, METALS TRANSITION (elements of groups 3A to 7A, 8, 1B and 2B) and elements of Group 3B, for the formation of an oxide (eg a ketone, an alcohol, a carboxylic acid) wherein R SUP 1 YR} SUP, 2} REPRESENT a substituent, E.G. A hydrogen atom or halogen, OR SUP, 1} YR SUP, 2} STATES MAY BE ONE CYCLE double bond or aromatic or nonaromatic 5 to 12 MEMBER IS OO X OH n is a number between 1 and 3.