Covalent anchoring of 1,4‐dimethyl‐1,4,7‐triazacyclononane on silica gel is the first step in the preparation of a heterogenized Mn catalyst. When H2O2 is used as the oxidant, this material can catalyze the vicinal cis‐dihydroxylation of disubstituted olefins, as shown schematically here. Both enantiomers of the product are obtained.