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Combining computations and X-ray structure analysis we have demonstrated that [Pt(CN4)]2− can behave as a Lewis acid inside an enzyme's cavity. The nature of a counterintuitive contact found between a catalytically active GLN residue belonging to a mitochondrial synthase and the Pt(II) center was investigated by combining molecular dynamics and quantum mechanics calculations. Results confirm the electron acceptor role of [Pt(CN4)]2−, serving as an inspiration for the design of biomolecular cages able to tweak the nucleophilic/electrophilic character of an organometallic compound. [ABSTRACT FROM AUTHOR]

This feature article highlights the discovery and development of phosphanoxyl complex chemistry starting from (neutral) low-coordinate phosphorus radicals and the quest of metal ligation effects. We describe synthesis and reactions of precursors, namely 2,2,6,6-tetramethylpiperidinoxyl (TEMPO) substituted phosphane tungsten(0) complexes. Trapping reactions of transient phosphanoxyl complexes, formed via thermal homolytic N–O bond cleavage, as well as their use in radical polymerisations are illustrated, thus revealing an interesting reactivity dichotomy. DFT calculations provide insight into thermal stabilities of precursors and the resulting spin density distributions (SDDs) in these reactive intermediates. Systematic studies on the dependance of the electron delocalisation in phosphanoxyl complexes have been performed examining different substitution pattern at phosphorus and different co-ligand combinations at the tungsten(0) center. Preliminary results on Mn and Fe complexes are reported. [ABSTRACT FROM AUTHOR]

Herein we report experimental evidence for the shortest intermolecular distance reported for two electronically-different hydrogen atoms in the solid state. The Hδ+⋯Hδ− non-covalent interaction was studied using theoretical calculations indicating that electrostatic and dispersion forces are of paramount importance. [ABSTRACT FROM AUTHOR]

The generality of nucleophilic iodonium interactions (NIIs) has been demonstrated by preparing a range of silver(I) and iodonium (I+) complexes and studying their 15N NMR chemical shifts, with the first example of a NII-complex involving a 2-coordinate silver(I) complex being confirmed by X-ray crystallography, and its nucleophilicity studied by DFT calculations. [ABSTRACT FROM AUTHOR]

A combined CSD and ab initio study reveals that the interaction between the sp³ C-atom in para-substituted ArCF3 and electron rich atoms is weak (<5 kcal mol-1), somewhat directional, and thus comparable to CH-π interactions. [ABSTRACT FROM AUTHOR]

Retraction of 'Nucleophilic iodonium interactions (NIIs) in 2-coordinate iodine(I) and silver(I) complexes' by Jas S. Ward et al., Chem. Commun., 2021, 57, 5094–5097, DOI: 10.1039/D1CC01505B. [ABSTRACT FROM AUTHOR]

New 1–2 nm macrocyclic iodine(I) complexes prepared VIA a simple ligand exchange reaction manifest rigid 0.5–1 nm cavities that bind the hexafluorophosphate anion in the gas phase. The size of the cavities and the electrostatic interactions with the iodine(I) cations influence the anion binding properties of these macrocyclic complexes. [ABSTRACT FROM AUTHOR]

A doubly-interlocked [2]catenane – or Solomon link – undergoes a complex conformational change upon addition of sulfate in methanol. This transformation generates a single pocket where two SO42− anions bind through multiple hydrogen bonds and electrostatic interactions. Despite the close proximity of the two anions, binding is highly cooperative. [ABSTRACT FROM AUTHOR]

The first asymmetric halogen-bonded iodonium complexes [I(py)(4-DMAP)]PF6 (2c) and [I(py)(4-Etpy)]PF6 (2e) were prepared via [N–Ag–N]+ → [N–I–N]+ cation exchange of their analogous 2-coordinate silver complexes. The complexes were characterised by 1H and 1H–15N HMBC NMR spectroscopy, and single crystal X-ray crystallography. [ABSTRACT FROM AUTHOR]

Cocrystallization of a bis[1-(4-pyridyl)butane-1,3-dionato]copper(II) (1) complex and 1,4-diiodoperfluorobenzene in the presence of pyridine yields a 1 : 1 cocrystal where both the σ and π-holes of 1,4-diiodoperfluorobenzene play a role. The crystal structure shows short arene CuO4⋯π-hole stacking contacts, where the {dz2-CuIIO4} moiety functions as an integrated five-center π-hole acceptor. DFT calculations combined with quantum theory of atoms-in-molecules and noncovalent interaction plot analyses corroborated the structure-defining role of the {dz2-CuIIO4}⋯π-hole contacts. [ABSTRACT FROM AUTHOR]

Single crystal X-ray analyses show that iodine in pyridinium periodates acts as a halogen bond (HaB) donor forming short and almost linear contacts with neutral and anionic electron donors. A combination of QTAIM and NCIplot computational tools proves the attractive nature of these contacts. [ABSTRACT FROM AUTHOR]

The interaction of a [bis(pyridine)iodine(I)]+ cation with a [bis(pyridine)silver(I)]+ cation, in which an iodonium ion acts as a nucleophile by transferring electron density to the silver(I) cation, is reinvestigated herein. No measurable interaction is observed between the cationic species in solution by NMR; DFT reveals that if there is an attractive interaction between these complexes in solution, it is dominantly the π–π interaction of pyridines. [ABSTRACT FROM AUTHOR]

The X-ray structure of the {Cu(NH3)4[Au(CN)2]}+[Au(CN)2]− salt is reported showing an unprecedented [d9]Cu⋯[d10]Au coinage bond. The physical nature of the interaction has been studied using DFT calculations, including the quantum theory of atoms-in-molecules, the noncovalent interaction plot and the natural bond orbital analysis, revealing the nucleophilic role of the [d10]Au metal and the electrophilic role of [d9]Cu metal. [ABSTRACT FROM AUTHOR]

A statistical survey of the Cambridge Structural Database reveals that the interaction between the π-holes of nitro groups and electron-rich atoms is somewhat directional. High-level ab initio computations indicate energies up to −6.6 kcal mol−1. [ABSTRACT FROM AUTHOR]

Herein we report the synthesis and X-ray characterization of a gold(III) complex of 1-hexylcytosine via N(3). The AuCl3N complexes stack on top of each other by reciprocal [Au⋯Cl] regium bonding interactions. After the first example 35 years ago, this is the second available structure of a cytosine nucleobase model complexed to gold(III). [ABSTRACT FROM AUTHOR]

Key findings regarding the effects of ligand preorganisation via halogen bonding on the outcome of reactions at rhodium are reported. An unprecedented halogen bonding-mediated oxidative addition of CAr–I bonds to rhodium with efficient formation of cyclometallated species deserves special mention. [ABSTRACT FROM AUTHOR]

Herein we report the experimental observation (X-ray characterization) of two different binding modes in H-bonded anion–anion complexes (anion = citrate) in N-(1-(2-phenylethyl)-4-piperidinylium)-N-phenyl-propanamide-citrate (fentanyl citrate). High level DFT calculations indicate that both types of anion–anion complexes (one with two and the other with four H-bonds) are thermodynamically unstable but kinetically stable with respect to the isolated anions with activation barriers as high as 14 kcal mol−1. [ABSTRACT FROM AUTHOR]

Herein we report the experimental observation (X-ray characterization) of an anion–anion complex (anion = hydrogen fumarate) stabilized by H-bonds that is trapped in a secondary squaramide receptor. High level ab initio calculations indicate that the anion–anion complex is thermodynamically unstable but kinetically stable with respect to the isolated anions. [ABSTRACT FROM AUTHOR]

A novel ambiguous reactivity of Li/Cl phosphinidenoid complexes under redox conditions is described. The outcome of the reaction with hexafluoroacetone is highly dependent on the P-substituent as fluoride substitution occurred in the case of R = CPh3 and C5Me5via a radical pathway, whereas for R = CH(SiMe3)2 a complex having a novel 1,2-diol-type P-ligand was obtained via a closed-shell pathway. DFT calculations reveal a new SET pathway starting with a noncovalent π-hole complex between the phosphinidenoid anion and hexafluoroacetone followed by an elimination of LiF. The second, closed-shell reaction course is strongly influenced by a noncovalent O…Si interaction established after the initial nucleophilic attack. [ABSTRACT FROM AUTHOR]

A novel thiocyanate bridged 2D MOF, [CdL(μ-1,3-SCN)2]n, [HL = 2-(2-(ethylamino)ethyliminomethyl)-6-ethoxyphenol] has been synthesized and characterized by X-ray crystallography. The band gap of the synthesized material in the solid state has been determined by experimental measurements and compared with the theoretical value obtained from DFT calculations. For the first time, the single crystal X-ray crystallography of a MOF has been reported along with its applicability in photosensitive devices. [ABSTRACT FROM AUTHOR]

Bis-pyridazine tectons support the structure of metallosupramolecular cavitand Cu2L44+, which is capable of selective encapsulation of SiF62− anions by a set of multiple host–guest interactions. [ABSTRACT FROM AUTHOR]

An easy reversible switching of the electronic ground state in a pentacoordinated copper(ii) complex is reported for the first time. The simple protonation of a carboxylic group in a Cu(ii) complex with a {dx2−y2}1 electronic configuration leads to a flip of the ground electronic configuration from {dx2−y2}1 to {dz2}1 in the metal ion. [ABSTRACT FROM AUTHOR]

Two self-assembled hosts are formed from Ag(i) salts and bis-pyrimidyl ligands and X-ray characterized. Both are able to incorporate two anions into the structure combining hydrogen bonding and electrostatic interactions. [ABSTRACT FROM AUTHOR]