The present invention relates to a process for producing phenol and a ketone of general formula R1COCH2R3 (I), in which R1 and R2 each independently represent an alkyl group having from 1 to 4 carbon atoms, said process comprising: (a) providing an alkylbenzene feedstock comprising (i) an alkylbenzene of general formula (II) in which R1 and R2 have the same meaning as in formula (I) and (ii) at least one structural isomer of said alkylbenzene of formula (II) in an amount of at least 0.7% of the weight of alkylbenzene of formula (II), (b) submitting the alkylbenzene feedstock to oxidation conditions in the presence of oxygen and in the presence of a cyclic imide of formula (III): in which X represents a carbonyl (CO) group or a sulfonyl (SO2) group, n is 0, 1, 2, 3 or 4, R3 is one or several groups selected from a hydrogen atom, a halogen atom, an alkyl group, an alkoxy group, an amino group and R4 is a hydrogen atom, an alkaline metal cation or an alkaline earth metal cation, or in the presence of N,N′,N″-trihydroxyisocyanuric acid (THICA), to produce a product comprising a hydroperoxide of general formula (IV) in which R1 and R2 have the same meaning as in formula (I), and (c) converting the hydroperoxide of formula (IV) into phenol and a ketone of formula (I).