Dear Colleagues,

Organometallic homogeneous catalysts (OHCs), named in this way to differentiate them from organometallic supported catalysts, have become essential tools in organic synthesis, especially in the production of fine chemicals. One of the advantages of OHCs is their selectivity, which allows the formation of the desired products with high performance. This is due to their ability to promote the selective activation of C−E (where E = H or heteroatom) bonds and subsequent coupling reactions. There are several reasons behind the high performance of OHCs, among which the following stand out: i) the great variability of oxidation and coordination numbers that are found in transition metal complexes, ii) the ability of transition-metal-based catalysts to reversibly change between oxidation states and coordination numbers during a catalytic process, and iii) the fact that the performance of OHCs can be easily tuned by varying the electronic and/or steric properties of the active site (nature of the ligands). The use of OHCs has allowed the development of environmentally benign catalytic processes for obtaining polymers, allylic acetates, alcohols, aldehydes, ketones, and esters in good yields, with high stereoselectivity, and at an industrial scale by catalytic oxidation, hydroformylation, polymerization, metathesis, and a range of other transformative processes. Moreover, OHCs have been successfully employed at laboratory scale in CO₂ reduction processes, selective dehydrogenation of formic acid, and nitrogen fixation processes, among others.

This Special Issue aims to show the state-of-the-art and future applications of OHCs and includes experimental and theoretical studies as well as revisions.

• homogeneous catalysis
• sustainable chemistry
• small molecule activation
• CO2 valorization
• hydrogenation
• hydroformylation
• hydroamination
• hydrosilylation
• carboxylation
• polymerization