Large differences in the ratio of sulfide versus sulfoxide oxidation of thianthrene 5-oxide (SSO) have been observed for heterogeneous versus homogeneous Ti-IV catalysts; whereas the Ti-doped zeolites (heterogeneous) oxidise by means of an electrophilic species, sulfoxide coordination (template effect) fos Ti(OiPr)(4) (homogeneous) masks the true electrophilic character of the metal oxidant.