A Well‐Defined Anionic Dicopper(I) Monohydride Complex that Reacts like a Cluster**

Abstract

Low-nuclearity copper hydrides are rare and few well-defined dicopper hydrides have been reported. Herein, we describe the first example of a structurally characterized anionic dicopper hydride complex. This complex does not display typical reactivity associated with low-nuclearity copper hydrides, such as alcoholysis or insertion reactions. Instead, its stoichiometric and catalytic reactivity is akin to that of copper hydride clusters. The distinct reactivity is ascribed to the robust dinuclear core that is bound tightly within the dinucleating ligand scaffold.

Persistence of a Ru3(μ‐CO)3(CO)5Cluster Bound to a PNNP “Expanded Pincer” Ligand in Different Protonation States

“…The 1 H NMR spectrum displays two naphthyridine doublet resonances at δ =5.60 and 5.28 ppm, which are shifted upfield compared to compound 1 and 2 (see Figure S20). This upfield shift and symmetry of the naphthyridine backbone are key indicators of a fully dearomatized t Bu PNNP** ligand [8,16] . Based on these observations we propose that this species contains a fully dearomatized t Bu PNNP** ligand as depicted in Scheme 4.…”

“…This upfield shift and symmetry of the naphthyridine backbone are key indicators of a fully dearomatized tBu PNNP** ligand. [8,16] Based on these observations we propose that this species contains a fully dearomatized tBu PNNP** ligand as depicted in Scheme 4. Unfortunately, the reactive nature of this highly basic species prevented its isolation (see ESI).…”

“…Recently, we reported how a combination of 18-crown-6 and KOtBu provides access to an anionic dicopper hydride featuring a dianionic tBu PNNP** ligand. [16] Hence, with the goal to generate a tBu PNNP** ligand on the triruthenium carbonyl cluster we treated a THF suspension of 1 with a THF solution containing two equiv. KOtBu and two equiv.…”

Quantification of the Steric Properties of 1,8-Naphthyridine-Based Ligands in Dinuclear Complexes

“…The former approach has previously been used for dinuclear cobalt and ruthenium complexes in which the metal centers are not in close proximity. , In these reports, the sterics of the full core of the molecule are qualitatively analyzed using V bur steric encumbrance maps with a sphere size encompassing the whole molecule. On the other hand, reports on dinuclear 1,8-naphthyridine complexes, in which the metal atoms are in close proximity of each other, have shown that auxiliary ligands or substrates tend to bind in the center between the two metal centers. ,,,− It therefore reflects the reactivity of these complexes better to choose the center of the binding pocket, in the middle of the two metal atoms, as the origin of the sphere for V bur calculations (Figure ). The standard sphere diameter for mononuclear complexes is 3.5 Å; however, for a dinuclear binding pocket, the sphere size should be larger to encompass both metals and their surroundings sufficiently.…”

Quantification of the Steric Properties of 1,8-Naphthyridine Based Ligands in Dinuclear Complexes

“…On the other hand, reports on dinuclear 1,8naphthyridine complexes in which the metal atoms are in close proximity of each other, have shown that auxiliary ligands or substrates tend to bind in the center between the two metal centers. [22,28,32,[34][35][36][37][38] It therefore reflects the reactivity of these complexes better to choose the center of the binding pocket, in the middle of the two metal atoms, as the origin of the sphere for Vbur calculations (Figure 2). The standard sphere diameter for mononuclear complexes is 3.5 Å, [39] however, for a dinuclear binding pocket the sphere size should be larger to encompass both metals and their surroundings sufficiently.…”