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It remains a great challenge to achieve polar order in organic molecular crystals because anti‐parallel alignment of side‐by‐side molecules is intrinsically preferred. We have addressed this problem with a rational design that focuses on the polar stacking of parallel beloamphiphile monolayers (PBAMs) with strong lateral quadrupole‐quadrupole attractions. We employ arene‐arene interactions as lateral synthons. The first successes were achieved with unsymmetrical donor (X), acceptor (Y) substituted acetophenone azines which form polar PBAMs with double T‐contacts between the azines. Near‐perfect alignment was achieved with the methoxy series of (MeO, Y)‐azines with Y=Cl, Br, I. Here, we report on the synthesis, the characterization (GC/MS, 1H NMR, 13C NMR, FTIR), the crystallization, and the single‐crystal X‐ray analyses of the phenoxy series of (PhO, Y)‐acetophenone azines with Y=F, Cl, Br, I. Properties of (RO, Y) azines were computed at the APFD/6‐311G* level and are discussed with reference to p‐nitroaniline (PNA). This (PhO, Y) series embodies an improved PBAM design based on triple T‐contacts which is shown to facilitate faster crystallization and to produce larger crystals. Perfect polar‐alignment has been achieved for the phenoxy series of (PhO, Y)‐azines with Y=Cl, Br, I and the (PhO, F)‐azine also features near‐perfect dipole alignment. [ABSTRACT FROM AUTHOR]

N‐alkylation of 5‐hydroxynicotinic acid esters with electrophiles containing diene functionality produces salts that undergo intramolecular (4+3) cycloaddition reactions upon heating in the presence of base. Initial studies used a three‐carbon tether to join the pyridinium ion and diene, revealing some aspects of the inherent selectivity of the reaction with such substrates. Much more challenging was the synthesis of related species possessing only a two‐carbon tether. Nevertheless, the cycloaddition of such compounds was successful, leading directly to the ABC ring system of the alkaloid daphnicyclidin A. [ABSTRACT FROM AUTHOR]

The coordination of tBuNC and CO with the diarsenido complexes (C5Me5)2An(η2‐As2Mes2), An=Th, U, has been investigated. For the first time, a comparison between isostructural complexes of ThIV and UIV has been possible with CO; density functional calculations indicated an appreciable amount of π backbonding that originates from charge transfer from an actinide‐arsenic sigma bond. The calculated CO stretching frequencies in the ThIV and UIV diarsenido complexes are consistent with the experimental measurements, both show large shifts to lower frequency. We demonstrate that the π backbonding is crucial to explaining the red shifts of CO frequency upon AnIV complex formation. Interestingly, this interaction essentially correlates to the parallel orientation of π*(C−O) orbitals relative to the An−As bond. [ABSTRACT FROM AUTHOR]

Access to lanthanide acetate coordination compounds is challenged by the tendency of lanthanides to coordinate water and the plethora of acetate coordination modes. A straightforward, reproducible synthetic procedure by treating lanthanide chloride hydrates with defined ratios of the ionic liquid (IL) 1‐ethyl‐3‐methylimidazolium acetate ([C2mim][OAc]) has been developed. This reaction pathway leads to two isostructural crystalline anhydrous coordination complexes, the polymeric [C2mim]n[{Ln2(OAc)7}n] and the dimeric [C2mim]2[Ln2(OAc)8], based on the ion size and the ratio of IL used. A reaction with an IL : Ln‐salt ratio of 5 : 1, where Ln=Nd, Sm, and Gd, led exclusively to the polymer, whilst for the heaviest lanthanides (Dy−Lu) the dimer was observed. Reaction with Eu and Tb resulted in a mixture of both polymeric and dimeric forms. When the amount of IL and/or the size of the cation was increased, the reaction led to only the dimeric compound for all the lanthanide series. Crystallographic analyses of the resulting salts revealed three different types of metal‐acetate coordination modes where η2μκ2 is the most represented in both structure types. [ABSTRACT FROM AUTHOR]

We report the synthesis of a novel metal–organic capsule constructed from six pyrogallol[4]arene macrocycles, which are switched together by 16 FeIII and 16 CoII ions. This supramolecular structure is the first instance of a spheroidal heterometallic nanocage assembled through a one‐step metal–ligand coordination approach. This new assembly also demonstrates an important proof of concept through the formation of multiple heterometallic metal–metal interactions within the capsule framework. Photophysical and electrochemical studies of self‐assembled capsule films indicate their potential as semiconductors. These materials display unexpected photoelectric conversion properties, thus representing an emergent phenomenon in discrete metal–organic supramolecular assemblies. [ABSTRACT FROM AUTHOR]

A hexameric metal–organic nanocapsule is assembled from pyrogallol[4]arene units, which are stitched together with indium ions. This indium‐seamed capsule is the first instance of a M24L6 type hexameric coordination cage held together exclusively by trivalent metal ions. Explicitly, unlike previously reported pyrogallol[4]arene‐based metal‐seamed capsules, the current In3+ seamed capsule is entirely supported by O→In coordinate bonds. This work demonstrates the important proof of concept of the ability of pyrogallol[4]arene to react with metals in higher oxidation states to assemble into atomically‐precise hexameric coordination cages. As such, these results open up exciting avenues toward the assembly of previously unanticipated metal–organic capsules, for example offering inspiration for tackling metals exhibiting high valence states such as in the lanthanide and actinide series. [ABSTRACT FROM AUTHOR]

To extend organoactinide chemistry beyond uranium, reported here is the first structurally characterized transuranic hydrocarbyl complex, Np[η4‐Me2NC(H)C6H5]3 (1), from reaction of NpCl4(DME)2 with four equivalents of K[Me2NC(H)C6H5]. Unlike the UIII species, the neptunium analogue can be used to access other NpIII complexes. The reaction of 1 with three equivalents of HE2C(2,6‐Mes2‐C6H3) (E=O, S) yields [(2,6‐Mes2‐C6H3)CE2]3Np(THF)2, maintaining the trivalent oxidation state. [ABSTRACT FROM AUTHOR]

Many biologically important compounds are amphiphilic in character. Glycolipids, for example, represent a biologically important class of amphiphiles. Receptors and sensors for such compounds must also be amphiphilic making them a challenge to prepare. Here, a cucurbit[8]uril (CB[8])‐based sensor system has been prepared and tested for detection of amphiphilic compounds. This multi‐component system consists: a CB[8], which acts as a hydrophobic lipid receptor, a hydrophilic pyridinium‐based carbohydrate receptor, and a fluorescent indicator. The system self‐assembles in aqueous solution. The pyridinium quenches the fluorescence of the indicator giving a strong turn‐on response when it is displaced by the analyte. The sensor system was characterized by NMR, X‐ray crystallography, and fluorescence titrations. [ABSTRACT FROM AUTHOR]

The solubilities of the quadrupolar molecules benzene and CO2 in various ionic liquids (ILs) are compared in order to determine the connection between aromatic liquid clathrate formation and CO2 dissolution in ILs. It was found that both CO2 Henry's law constants and benzene solubility are remarkably well correlated with each other and with IL molar volume, suggesting both phenomena depend more on the strength of interionic interactions between the ions of an IL rather than the identity of either ion. However, IL ion-quadrupole interactions were found to have an effect for dicyanamide ([N(CN)2]−), where solubility of CO2 and benzene are affected by destabilizing and stabilizing interactions with [N(CN)2]−, respectively. The results suggest both solubility phenomena are related to the incorporation of the solute into an IL host network. Aromatic liquid clathrate formation thus has potential as a facile experimental probe for predicting the relative ability of ILs to physisorb CO2. [ABSTRACT FROM AUTHOR]

Boranes and boron hydrides are well known for their novel molecular structures and useful chemical reactivity, with [B9H14]− notable in particular for its ease of isolation, unusual structure, and tautomerization. We report an experimental and theoretical investigation of the structure of [B9H14]− and the energetics of some of its reactions. Salts of [B9H14]− with 1-ethyl-3-methylimidazolium and N-butyl- N-methylpyrrolidinium were characterized by single-crystal X-ray diffraction and demonstrate the stabilization of an isomer of [B9H14]− not previously observed in the solid state. Heats of formation and acid dissociation constants of [B9H14]− and closely related structures were calculated. The results suggest a mechanism for particularly energetic hypergolic ignition induced by protonation and suggest potential for reversible H2 storage. These results encourage further investigation of [B9H14]− as an energy-storage medium in ionic systems. [ABSTRACT FROM AUTHOR]

Carbon dioxide fixation with zinc complexes of the anionic tris(triazolyl)borate (Ttz) ligand offers biomimetic structures in a hydrophilic environment. However, the synthetic result depends greatly on the steric bulk of the Ttz ligand. Synthetic routes adapted from the synthesis of (Tp)ZnOH have been applied to bulky Ttz ligands, but side products often result because Ttz frequently forms complexes with +1 metals or cations used in the synthesis. Nonetheless, (Ttz tBu,Me)ZnOH ( 1) has been successfully synthesized and crystallographically characterized, but only via the hydrolysis of the zinc (hexamethylsilyl)azide complex ( 6). With less bulky ligands, namely TtzPh,Me, routes expected to form LZnOH lead instead to bis(ligand) products, namely [(TtzPh,Me)2Zn] ( 12). The use of ligands of intermediate steric bulk has led to the isolation of (Ttz iPr2)ZnOH ( 2a) which fixes atmospheric CO2 to produce [(Ttz iPr2)Zn]2(μ-η1-η2-CO3) ( 2b). This activation of CO2 from air is irreversible. We report the crystal structures of 2b and related molecules used for synthesis and structural comparison: (Ttz iPr2)ZnCl ( 7), [(Ttz iPr2)Cu(μ-OH)]2 ( 9), and [(Ttz iPr2)Cu(μ-Cl)]2 ( 10). [ABSTRACT FROM AUTHOR]

Cover Feature: Perfect Polar Alignment of Parallel Beloamphiphile Monolayers: Synthesis, Characterization, and Crystal Architectures of Unsymmetrical Phenoxy-Substituted Acetophenone Azines (ChemPlusChem 12/2022) Azines, crystal engineering, dipole parallel alignment, ferroelectric crystals, noncovalent interactions Keywords: azines; crystal engineering; dipole parallel alignment; ferroelectric crystals; noncovalent interactions EN azines crystal engineering dipole parallel alignment ferroelectric crystals noncovalent interactions 1 1 1 12/30/22 20221201 NES 221201 B The cover feature image shows b perfect dipole-parallel alignment in crystals of the phenoxy series of (PhO, Y)-acetophenone azines with Y=F, Cl, Br, I. The crystal architecture of these ferroelectric non-linear optical materials embodies a rational design that aims at the polar stacking of parallel beloamphiphile monolayers (PBAMs). [Extracted from the article]

Here we demonstrate that neat reactions of amphoteric azoles with more basic azoles give a family of finely tunable, nonstoichiometric liquids which are useful for N-donor coordination chemistry. Reacting 4,5-dicyanoimidazole (4,5-DCNIm) with 1-methylimidazole (1-mim) gives new compounds with composition-dependent speciation. Two crystalline compounds, a 1:1 protic salt, [H(1-mim)][4,5-DCNIm], and a 1:2 salt co-crystal, [H(1-mim)][4,5-DCNIm]⋅4,5-DCNIm, were isolated and structurally characterized, while differential scanning calorimetry revealed both suppression of crystallization and the presence of neutral and anionic species in the melt. Reactions of Cu(NO3)2⋅2.5 H2O, CuO, and ZnO with the neat 2:1 1-mim/4,5-DCNIm melt resulted in the isolation of entirely N-donor ligated complexes of the formula M(4,5-DCNIm)2(1-mim)4 (M=Cu, Zn). [ABSTRACT FROM AUTHOR]

Di- tert-butylneopentylphosphine (DTBNpP) and palladium(II) acetate provide an efficient catalytic system for the α-arylation of ketones. Aryl bromides were coupled with ketones using 0.25-0.5 mol-% Pd(OAc)2/DTBNpP in toluene at 50 °C, whereas aryl chlorides required a higher catalyst loading (0.5-2.0 mol-%) and a higher temperature (80 °C). Coupling of 2-bromophenol with ketones using the Pd/DTBNpP system provides an efficient route for the synthesis of benzofurans. [ABSTRACT FROM AUTHOR]

The article presents a study which examines failures of fractional crystallization. Searches for structures containing isomers and for co-crystals of very similar molecules were conducted. Findings of the study reveal that a list of 270 structures of ordered co-crystals of isomers and near isomers that are almost the same has been compiled.

Five structures of co-crystals grown from aqueous solutions equimolar in 15-crown-5 (or 15C5) and [ M(H2O)6](NO3) n, M = Al3+, Cr3+ and Pd2+, are reported. The hydrogen-bonding patterns in all are similar: metal complexes including the fragment trans-H2O- M-OH2 alternate with 15C5 molecules, to which they are hydrogen bonded, to form stacks. A literature survey shows that this hydrogen-bonding pattern is very common. In each of the two polymorphs of the compound [Al(H2O)6](NO3)3·15C5·4H2O there are two independent cations; one forms hydrogen bonds directly to the 15C5 molecules adjacent in the stack, while the other cation is hydrogen-bonded to two water molecules that act as spacers in the stack. These stacks are then crosslinked by hydrogen bonds formed by the three nitrate counterions and the three lattice water molecules. The hydrogen-bonded stacks in [Cr(H2O)5(NO3)](NO3)2·1.5(15C5)·H2O are discrete rather than infinite; each unit contains two Cr3+ complex cations and three 15C5 molecules. These units are again crosslinked by the uncoordinated nitrate ions and a lattice water molecule. In [Pd(H2O)2(NO3)2]·15C5 the infinite stacks are electrically neutral and are not crosslinked. In [Pd(H2O)2(NO3)2]·2(15C5)·2H2O·2HNO3 a discrete, uncharged unit containing one Pd complex and two 15C5 molecules is `capped off' at either end by a lattice water molecule and an included nitric acid molecule. In all five structures the infinite stacks or discrete units form an array that is at least approximately hexagonal. [ABSTRACT FROM AUTHOR]

Metal–Organic Capsules A mixed Fe3+/Co2+‐seamed capsule comprising multiple heterometallic metal–metal interactions is presented by Sisi Feng, Jerry L. Atwood et al. in their Communication on page 10516. This novel capsule displays unexpected semiconducting properties. [ABSTRACT FROM AUTHOR]

Schicksalswende: Unter oxidativen Bedingungen und der Verwendung von Iodosobenzol erlebt ein kürzlich beschriebenes Zwitterion eine „Wendung des Schicksals“. Die oxidative Cyclisierung einer Reihe von Fluoralkoxy ‐ funktionalisierten Imidazolium ‐ Verbindungen führt dabei zur Bildung von anellierten Imidazolonketalen. [ABSTRACT FROM AUTHOR]

A simple method to incorporate magnetite nanoparticles (Fe3O4 NPs) into cotton fiber for arsenic sorption is demonstrated. Choline acetate is utilized to simultaneously suspend Fe3O4 NPs while swelling the cotton fiber surface, allowing the incorporation of the Fe3O4 NPs in the fiber by dipping at 80 °C and washing with water. A 1:5 mass ratio Fe3O4 NPs:cotton fiber exhibits a tenfold increase in the sorption of As(V) when compared with raw cotton fiber. This method could be used to mass produce field‐deployable sorbents near polluted areas lacking water treatment infrastructure. [ABSTRACT FROM AUTHOR]

Stabile Harnstoffketale sind wegen ihrer Instabilität und Reaktivität nicht zugänglich. A. J. Arduengo III, J. W. Runyon et al. beschreiben nun in ihrer Zuschrift auf S. 11071 ff. die Oxidation einer Serie von Imidazoliumalkoxiden zu isolierbaren Imidazolon ‐ Spiroketalen. Die Spiralform dieses neuartigen anellierten Ringsystems erinnert an die Wendeltreppen im Shelby Hall Chemistry Building, in dem es hergestellt wurde. [ABSTRACT FROM AUTHOR]

Stable urea ketals have remained elusive because of their inherent instability and reactivity. In their Communication on page 10871 ff., A. J. Arduengo III, J. W. Runyon et al. describe the oxidation of a series of imidazolium alkoxides to produce isolable imidazolone spiroketals. The spiral nature of this novel fused‐ring system is reminiscent of the spiral staircases in the Shelby Hall Chemistry Building where it was created. [ABSTRACT FROM AUTHOR]

Five structures of co-crystals grown from aqueous solutions equimolar in 15-crown-5 (or 15C5) and [ M(H2O)6](NO3) n, M = Al3+, Cr3+ and Pd2+, are reported. The hydrogen-bonding patterns in all are similar: metal complexes including the fragment trans-H2O- M-OH2 alternate with 15C5 molecules, to which they are hydrogen bonded, to form stacks. A literature survey shows that this hydrogen-bonding pattern is very common. In each of the two polymorphs of the compound [Al(H2O)6](NO3)3·15C5·4H2O there are two independent cations; one forms hydrogen bonds directly to the 15C5 molecules adjacent in the stack, while the other cation is hydrogen-bonded to two water molecules that act as spacers in the stack. These stacks are then crosslinked by hydrogen bonds formed by the three nitrate counterions and the three lattice water molecules. The hydrogen-bonded stacks in [Cr(H2O)5(NO3)](NO3)2·1.5(15C5)·H2O are discrete rather than infinite; each unit contains two Cr3+ complex cations and three 15C5 molecules. These units are again crosslinked by the uncoordinated nitrate ions and a lattice water molecule. In [Pd(H2O)2(NO3)2]·15C5 the infinite stacks are electrically neutral and are not crosslinked. In [Pd(H2O)2(NO3)2]·2(15C5)·2H2O·2HNO3 a discrete, uncharged unit containing one Pd complex and two 15C5 molecules is `capped off' at either end by a lattice water molecule and an included nitric acid molecule. In all five structures the infinite stacks or discrete units form an array that is at least approximately hexagonal. [ABSTRACT FROM AUTHOR]

Five structures of co-crystals grown from aqueous solutions equimolar in 15-crown-5 (or 15C5) and [M(H(2)O)(6)](NO(3))(n), M = Al(3+), Cr(3+) and Pd(2+), are reported. The hydrogen-bonding patterns in all are similar: metal complexes including the fragment trans-H(2)O-M-OH(2) alternate with 15C5 molecules, to which they are hydrogen bonded, to form stacks. A literature survey shows that this hydrogen-bonding pattern is very common. In each of the two polymorphs of the compound [Al(H(2)O)(6)](NO(3))(3).15C5.4H(2)O there are two independent cations; one forms hydrogen bonds directly to the 15C5 molecules adjacent in the stack, while the other cation is hydrogen-bonded to two water molecules that act as spacers in the stack. These stacks are then crosslinked by hydrogen bonds formed by the three nitrate counterions and the three lattice water molecules. The hydrogen-bonded stacks in [Cr(H(2)O)(5)(NO(3))](NO(3))(2).1.5(15C5).H(2)O are discrete rather than infinite; each unit contains two Cr(3+) complex cations and three 15C5 molecules. These units are again crosslinked by the uncoordinated nitrate ions and a lattice water molecule. In [Pd(H(2)O)(2)(NO(3))(2)].15C5 the infinite stacks are electrically neutral and are not crosslinked. In [Pd(H(2)O)(2)(NO(3))(2)].2(15C5).2H(2)O.2HNO(3) a discrete, uncharged unit containing one Pd complex and two 15C5 molecules is ;capped off' at either end by a lattice water molecule and an included nitric acid molecule. In all five structures the infinite stacks or discrete units form an array that is at least approximately hexagonal.