AbstractIn the synthesis of p‐hydroxybenzonitrile as a herbicide intermediate the nitrile formation is the most important reaction step. Possible feed compounds could be pure p‐cresole, cresole mixtures or OH‐protected cresoles like methoxy‐ or acetoxytoluenes. The ammoxidation of m‐ and p‐methoxytoluene and a m,p‐methoxytoluene‐mixture over vanadium‐titanium oxide catalysts has been investigated using flow reactors in a temperature range of 630–703 K. On comparable reaction conditions the conversion of pure compounds leads to a higher selectivity of p‐methoxybenzonitrile (approx. 70%, conversion 85 mol‐%) than that of the m‐compound (only 35%, conversion 45 mol‐%). For synthesis of the p‐nitrile the feedstock can be p‐methoxytoluene obtained by methylation of p‐cresole, but it is also possible to use a m,p‐methoxytoluene mixture obtained by methylation of an industrial cresole mixture. The ammoxidation of such a mixture affords a higher reactivity of the p‐isomer and p‐methoxybenzonitrile as the main reaction product, whereas m‐methoxytoluene remains unreacted for the most part. Generally, the results obtained show that an amount of approx. 79% of the converted p‐methoxytoluene was transformed into p‐methoxybenzonitrile, whereas the corresponding transformation into the m‐isomer was lower than 36%. An important part of the m‐isomer