Coordinating Ability of Anions, Solvents, Amino Acids, and Gases towards Alkaline and Alkaline‐Earth Elements, Transition Metals, and Lanthanides

Abstract

After briefly reviewing the applications of the coordination ability indices proposed earlier for anions and solvents toward transition metals and lanthanides, a new analysis of crystal structures is applied now to a much larger number of coordinating species: anions (including those that are present in ionic solvents), solvents, amino acids, gases, and a sample of neutral ligands. The coordinating ability towards s‐block elements is now also considered. The effect of several factors on the coordinating ability will be discussed: (a) the charge of an anion, (b) the chelating nature of anions and solvents, (c) the degree of protonation of oxo‐anions, carboxylates and amino carboxylates, and (d) the substitution of hydrogen atoms by methyl groups in NH3, ethylenediamine, benzene, ethylene, pyridine and aldehydes. Hit parades of solvents and anions most commonly used in the areas of transition metal, s‐block and lanthanide chemistry are deduced from the statistics of their presence in crystal structures.

Experimental and Computational Studies on Quadruply Bonded Dimolybdenum Complexes with Terminal and Bridging Hydride Ligands

“…The lesser stability of the bisphosphine 1⋅PMe 3 complex is counterintuitive, as it is the most coordinating of the ligands considered. The coordinating ability index for those ligands [34, 35] are 2.9, 1.3, and −0.3 for PMe 3 , thf, and pyridine, respectively (or, equivalently, coordination probabilities of 99.9, 95, and 32 %), and the relative stability would be expected to be the reverse of the trends found for the calculated Gibbs formation energies. Such a counterintuitive effect can be explained by carefully comparing the optimized structures of [Mo 2 (H) 2 (μ‐Ad Dipp2 ) 2 ] and [Mo 2 (H) 2 (μ‐Ad Dipp2 ) 2 (L) 2 ] (L=py, thf, PMe 3 ).…”

Molecular Solar Thermal Batteries through Combination of Magnetic Nanoparticle Catalysts and Tailored Norbornadiene Photoswitches

“…However,w ec ould observe as olvent-dependent difference in the speed of the back-conversion. In acetonitrile the back-conversion wass ignificantly slower,w hich is probably ar esult of the stronger competing coordination of acetonitrile compared with chloroform to the cobalt catalyst, [26] as wella sa ni nfluence of the solvent on the isomerization itself. The latter trend was also observed for several substituted derivatives of NBD by Moth-Poulsen and co-workers.…”

An Ion‐Pairing Approach to Stereoselective Metal‐Free Ring‐Opening Metathesis Polymerization

“…Our motivations to move away from dichloromethane, toward less hazardous solvents as well as bulk polymerizations,first led us to consider different counteranions of the pyrylium salts to augment solubility.T oq uickly screen the influence of counteranions,w ef irst added several phasetransfer catalysts (PTCs), [33][34][35] as shown in Table S1 ), each yielded PNB in high conversion. Conversely,a ddition of PTCs with more strongly coordinating anions like chloride, bromide,and nitrate,which are usually more nucleophilic, [36] failed to yield any detectable amount of PNB.N ucleophilic attack by anions on the pyrylium cation or radical cationic intermediates likely precluded polymerization in these latter cases.…”