Novel well-defined NNP and PNP manganese pincer complexes have been synthetized and fully characterized. The catalyst Mn-2 containing an imidazolyaminolphosphino ligand shows high activity and selectivity in the hydrogenation of a wide range of secondary and tertiary amides to the corresponding alcohols and amines, under relatively mild conditions. For the first time, more challenging substrates like primary aromatic amides including an actual herbicide can also be hydrogenated using this earth-abundant metal-based pincer catalyst.

Homogeneous catalytic systems are able to promote either the dehydrogenation of aqueous methanol to hydrogen and CO₂ or the hydrogenation of CO₂ to methanol and water. Here, we review and discuss these recent developments in this field.

The use of renewable energy is central for the realization of a circular economy, which is essential for further global economic development. In this background, hydrogen storage materials play an important role. Here we propose a previously overlooked, industrially available bulk chemical (methyl formate, MF) as an efficient and practical hydrogen storage material. Utilizing appropriate catalysts, hydrogen production from MF is significantly faster than with other established chemical hydrogen carriers, such as formic acid and methanol, under very mild conditions. The optimized MF dehydrogenation system presented here is highly active (maximum turnover frequency (TOF_max) > 44,000 h⁻¹ and turnover number > 100,000) and selective (CO undetectable). Moreover, the solvent-free MF dehydrogenation demonstrates its application potential. Here we show the dehydrogenation reaction of MF. We expect that these insights will serve as an inspiration for the development of alternative energy materials and new catalytic transformations.

[Ru(acac) ₃ ]/Triphos in combination with Yb(OTf) ₃ constitutes an improved catalyst system for the hydrogenation of aliphatic and aromatic secondary and tertiary amides.

Formic acid dehydrogenation (FAD) is considered as a promising process in the context of hydrogen storage. Its low toxicity, availability and convenient handling make FA attractive as a potential hydrogen carrier. To date, most promising catalysts have been based on noble metals, such as ruthenium and iridium. Efficient non-noble metal systems like iron were designed but manganese remains relatively unexplored for this transformation. In this work, we present a panel of phosphine free manganese catalysts which showed activity and stability in formic acid dehydrogenation. The most promising results were obtained with Mn(pyridine-imidazoline)(CO)₃Br yielding >14 l of the H₂/CO₂ mixture and proved to be stable for more than 3 days. Additionally, this study provides insights into the mechanism of formic acid dehydrogenation. Kinetic experiments, Kinetic Isotopic Effect (KIE), in situ observations, NMR labeling experiments and pH monitoring allow us to propose a catalytic cycle for this transformation.