The aim of Action D24 was to develop new transition metal-catalysed reactions with special emphasis on stereoselectivity to strengthen their application in chemical, biotechnological, pharmacological and environmental sciences. This objective was pursued by research to discover new transition metal-derived catalysts which provide high activity and enantioselectivity for a number of organic transformations. Transition metals compare very favourably as catalysts due to their non-toxicity, stability to various reaction conditions and ease of preparation and handling. Furthermore, the reactivity and selectivity of the metal catalyst can easily be tuned and refined by complexation to an organic ligand which makes it possible to design and test catalysts for a specific purpose and primarily those of importance to synthetic chemists. Among a large number of achievements, D24 has developed a new type of palladium-catalysed pseudo-domino process as a new synthetic route to pyrrolidones. A new palladium-catalysed synthesis of sulfoxides via addition of sulfenate anions has also been developed. An air-stable equivalent of trimethyl aluminium that is being applied in asymmetric methylations has also been produced and is now sold commercially. Action D24 has also focused on the synthesis of new chiral nitrogen-containing ligands for asymmetric catalysis and as a result of these studies a new synthetic procedure for the preparation of o-substituted triarylphenols has been developed. The application of new ligands in asymmetric heterogeneous catalysis, particularly asymmetric hydrogenation, has also been the subject of intensive studies by this Action. D24 has also greatly contributed toward the development of ruthenium chemistry for stereoselective organic synthesis, with particular emphasis on reactions which proceed with atom economy and improved efficiency, stereoselectivity, and eco-compatibility. Action D24 comprised members from more that 80 research institutions belonging to 22 different countries. The scientific achievements of D24 have been disseminated largely through various Action-organised ‘Stereocat’ workshops, numerous presentations at other international conferences, and a vast number of research papers published in peer-reviewed journals.
