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A general protocol for the selective hydrogenation and deuteration of a variety of alkenes is presented. Key to success for these reactions is the use of a specific nickel-graphitic shell-based core���shell-structured catalyst, which is conveniently prepared by impregnation and subsequent calcination of nickel nitrate on carbon at 450 ��C under argon. Applying this nanostructured catalyst, both terminal and internal alkenes, which are of industrial and commercial importance, were selectively hydrogenated and deuterated at ambient conditions (room temperature, using 1 bar hydrogen or 1 bar deuterium), giving access to the corresponding alkanes and deuterium-labeled alkanes in good to excellent yields. The synthetic utility and practicability of this Ni-based hydrogenation protocol is demonstrated by gram-scale reactions as well as efficient catalyst recycling experiments. �� 2021 The Authors. Angewandte Chemie International Edition published by Wiley-VCH GmbH

In the context of a carbon neutral economy, catalytic CO2 hydrogenation to methanol is one crucial technology for CO2 mitigation providing solutions for manufacturing future fuels, chemicals, and materials. However, most of the presently known catalyst systems are used at temperatures over 220 degrees C, which limits the theoretical yield of methanol production due to the exothermic nature of this transformation. In this review, we summarize state-of-the-art catalysts, focusing on the rationales behind, for CO2 hydrogenation to methanol at temperatures lower than 170 degrees C. Both hydrogenation with homogeneous and heterogeneous catalysts is covered. Typically, additives (alcohols, amines or aminoalcohols) are used to transform CO2 into intermediates, which can further be reduced into methanol. In the first part, molecular catalysts are discussed, organized into: (1) monofunctional, (2) M/NH bifunctional, and (3) aromatization-dearomatization bifunctional molecular catalysts. In the second part, heterogeneous catalysts are elaborated, organized into: (1) metal/metal or metal/support, (2) active-site/N or active-site/OH bifunctional heterogeneous catalysts, and (3) cooperation of catalysts and additives in a tandem process via crucial intermediates. Although many insights have been gained in this transformation, in particular for molecular catalysts, the mechanisms in the presence of heterogeneous catalysts remain descriptive and insights unclear.

Die Katalyse ist ein sehr komplexes und interdisziplinäres wissenschaftliches Gebiet, das die effiziente Herstellung einer Vielzahl von Produkten für verschiedene Branchen und in unterschiedlichen Produktionsgrößen ermöglicht. Somit ist die Katalyse eine der Schlüsseltechnologien zur Bewältigung wesentlicher Herausforderungen wie einer nachhaltigen Energieversorgung oder des Klimawandels. Das Datenmanagement in der Katalyse ist derzeit überwiegend auf institutioneller oder Arbeitsgruppenebene organisiert und basiert auf lokalen Konventionen. Übergreifende Repositorien und Standards, wie Daten inklusive Metadaten gespeichert werden sollen, existieren nur in rudimentärer Form. Um den höchstmöglichen Mehrwert aus der Katalyseforschung zu generieren, ist ein grundlegender Wandel in der Katalyseforschung und den katalyseverwandten Wissenschaften wie Chemieingenieurwesen und Verfahrenstechnik erforderlich. Die verschiedenen Disziplinen der Katalyse im Hinblick auf das Datenmanagement zusammenzuführen, ist die zentrale Herausforderung. Aus all diesen Notwendigkeiten heraus wurde im Rahmen der Initiative zur Nationalen Forschungsdateninfrastruktur (NFDI) das NFDI4Cat-Konsortium gegründet. Als eines von derzeit neun geförderten Konsortien konzentriert sich NFDI4Cat auf die Wissenschaften rund um die Katalyse. Dieser Artikel beschreibt die Motivation der Gründungsmitglieder für dieses im Oktober 2020 gestartete Konsortium und wie die Ziele in Bezug auf die Fachcommunity, die technische Infrastruktur und insbesondere das Forschungsdatenmanagement erreicht werden sollen. Darüber hinaus eröffnet die dynamische Entwicklung moderner Technologien zur Erfassung, Bereitstellung und zur Analyse großer Datenmengen neue Möglichkeiten für wissenschaftlichen Fortschritt in den Einzeldisziplinen und insbesondere an deren Nahtstellen.

Ruthenium PNP pincer complexes bearing supplementary cyclometalated C,N-bound ligands have been prepared and fully characterized for the first time. By replacing CO and H��� as ancillary ligands in such complexes, additional electronic and steric modifications of this topical class of catalysts are possible. The advantages of the new catalysts are demonstrated in the general ��-alkylation of ketones with alcohols following a hydrogen autotransfer protocol. Herein, various aliphatic and benzylic alcohols were applied as green alkylating agents for ketones bearing aromatic, heteroaromatic or aliphatic substituents as well as cyclic ones. Mechanistic investigations revealed that during catalysis, Ru carboxylate complexes are predominantly formed whereas neither the PNP nor the CN ligand are released from the catalyst in significant amounts. �� 2020 The Authors. Published by Wiley-VCH Verlag GmbH & Co. KGaA.

A straightforward methodology for the synthesis of anti-Markovnikov-type alcohols is presented. By using a specific cobalt triphos complex in the presence of Zn(OTf)2 as an additive, the hydrogenation of epoxides proceeds with high yields and selectivities. The described protocol shows a broad substrate scope, including multi-substituted internal and terminal epoxides, as well as a good functional-group tolerance. Various natural-product derivatives, including steroids, terpenoids, and sesquiterpenoids, gave access to the corresponding alcohols in moderate-to-excellent yields. �� 2020 The Authors. Published by Wiley-VCH Verlag GmbH & Co. KGaA.