Starting with the system proposed by Jenner, we wished to quantify the amount of methane produced in the absence of CO, upon decomposition of methyl formate with [Ru3(CO)12]: When methyl formate is heated at 160 °C in the presence of 3 mol% of [Ru3(CO)12] and 20 mol% of LiI in THF, we observed after 24 h a conversion of 55 %, however forming 14 % of methanol and 13 % of methyl iodide, from the decarbonylation and nucleophilic substitution of methylformate respectively. No other product was observed in 1 H NMR, leading us to conclude that the remainder consisted of methane and CO2, both identifiable in the NMR spectrum and GC chromatogram. The decarboxylation reaction thus led to the formation of methane in 28 % yield. In order to improve the efficiency and the selectivity, we considered a plausible mechanism with intertwined catalytic cycles that involve: (i) facilitating the cleavage of the C-O bond of methyl formate by nucleophilic substitution, using lithium iodide, to form methyl iodide and lithium formate, (ii) decarboxylating the formate on the catalyst to form a metal hydride intermediate and (iii), transferring this hydride equivalent to methyl iodide, yielding methane (Scheme ). Scheme 3: Proposed mechanism for the formation of methane from methyl formate CH3I (%) CH3OH (%) CH4 (%) 1 - 9 - 10 [a] Determined by 1 H RMN of crude mixture, mesitylene was used as internal standard, [b] computed by difference between conversion and yield of liquid products (ESI for more details), [c] reaction time of 24 h, [d] 100°C, [e] degradation of acetonitrile, [f] CH3Br