– 473 K) and ambient pressures has been previously demonstrated,39,40 including a prior report from our group evidencing participation of every single MIL-100 tri-iron node towards methanol formation,35 unlike iron-zeolites that typically carry distributions of active and inactive multinuclear iron centers.46–49 In this study, we use a suite of spectroscopic, transient kinetic, and site titration tools to relate metal oxidation state to reactive function. Specifically, the role of Fe2+ and Fe3+ sites in methanol and CO2 formation are identified. Altering the identity of the metal from iron to chromium enables C-C bond formation events that appear to involve methoxy intermediates that also mediate methanol formation over both MIL-100(M) variants. To this end, we elucidate in Section 3.1 the identity of sites involved in CO2 and methanol formation, identify in Section 3.2 the role of methoxy intermediates, demonstrate the propensity towards and methods for controlling the prevalence of C-C bond formation over MIL-100(Cr) in Section 3.3, before clarifying the diversity of functionality of Fe3+-methoxies in Section 3.4 The study captures how precise control over metal identity and oxidation state, combined with manipulation of the relative velocity of water and methanol concentration fronts, enables control not only over the selectivity towards desired partial oxidation products such as methanol (versus CO2) but also that towards C2 oxygenates (over C1 oxygenates).