The Activation of Dihydrogen

Facile Heterolytic H2 Activation by Amines and B(C6F5)3

“…The nodal character of the energetically accessible d orbitals allows a transition-metal center to react directly with H 2 in a concerted reaction with a low activation barrier. [2] However, not only are transitionmetal complexes expensive, but the complete removal of metal impurities from the reaction product is generally required in the production of pharmaceutical intermediates owing to toxicity concerns. [3] Although countless synthetic complexes and enzymes with transition metals at their reactive core are well known, there are significantly fewer examples of HÀH bond activation facilitated solely by a nonmetal.…”

Einfache heterolytische H2‐Aktivierung mit Aminen und B(C6F5)3

“…Wegen der Form der energetisch zugänglichen d-Orbitale des Übergangsmetallzentrums kann dieses direkt mit H 2 in einer konzertierten Reaktion über eine niedrige Aktivierungsbarriere reagieren. [2] Über-gangsmetallkomplexe sind aber nicht nur teuer, sondern bei der Produktion von pharmazeutischen Zwischenstufen müssen aus Toxizitätsgründen generell Metallverunreinigungen vollständig aus dem Reaktionsprodukt entfernt werden. [3] Während unzählige synthetische Komplexe und Enzyme mit Übergangsmetallen im reaktiven Zentrum die H-H-Bindung aktivieren, sind wesentlich weniger Systeme bekannt, in denen diese Aktivierung ausschließlich durch Nichtmetalle gelingt.…”

Reference Electrodes in Metal Corrosion

“…A carbon supported platinum catalyst is also used to produce hydrogen electrodes (GASKATEL, hydroflex electrode) [34]. This and the results of metal catalysis also confirm the catalytic character of equilibrium (10) [30][31][32][33][35][36][37][38][39][40][41][42][43][44].…”

“…There are many catalytic processes, where activation of the hydrogen molecule is a basic process. Surprisingly, there are even organic materials capable of activating dihydrogen (H 2 ) without transition metals [44][45][46]. On the other hand, it must be noted that these precious metals (platinum metals) used for making hydrogen electrodes are the best catalysts for molecular hydrogen activation, that is, for hydrogenation [18,19,[28][29][30][31][32][33][34][35][36][37][38][39][40][41][42][43][44][45][46].…”

“…In the field of metal catalysis, hydrogen electrode reaction (reaction (10)) is one of the most classic reactions studied from the beginning of the 20th century as a prototype of catalysis where electrodes act as catalysts [32]. It is well known that a hydrogen molecule (H 2 ) (sometimes called dihydrogen [37,44]) must be activated before any chemical process [30][31][32][33][35][36][37][38][39][40][41][42][43][44][45][46]. There are many catalytic processes, where activation of the hydrogen molecule is a basic process.…”