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p-Sulfonatocalix[5]arene forms host–guest complexes in the solid state with hydroxyl-functionalized imidazolium and bis-imidazolium cations, also involving gadolinium(III) ions which form a coordination polymer through the sulfonate groups of the calixarene. The interplay of the components have been investigated using Hirshfeld surface analysis, with the nature of the species in aqueous solution in the absence of the paramagnetic lanthanide ions studied using 1H NMR and modeled using molecular simulations.

The syntheses and crystallographically determined structures of metal complexes trans-[M(C≡CR)2Ln] (MLn= Ru(dppe)2, Ru{P(OEt)3}4, Pt(PEt3)2) featuring acetylide ligands further functionalized by aryl thioether groups are reported, together with those of analogous organic buta-1,3-diyne (RC≡CC≡CR) and 1,4-diethynylbenzene (RC≡CC6H4C≡CR) compounds for comparative purposes. The terminal thioether functional groups have an affinity for binding to the surface of gold electrodes and are considered as “anchor” groups in the design of molecules for study within metal|molecule|metal molecular junctions. The influence of the Lewis acidic and π-basic thioether moiety on a number of physical properties important to the electrical behavior of molecules within molecular junctions has been explored using spectroscopic, electrochemical, and quantum chemical methods. The thioether functional group serves as a moderately strong π-electron-donating substituent, similar in electronic character to the OMe group, resulting in relatively high lying HOMOs that are delocalized over the length of the molecule and well-suited to promote coherent tunneling within the junction. In addition, the facile oxidation processes and the relatively small reorganization energies associated with the one-electron oxidation of these compounds indicate the potential for effective hopping mechanisms of charge transport through longer structures based on these organometallic motifs.

Three Re(I) tricarbonyl complexes, with the general formulation Re(N^L)(CO)3X (where N^L is a bidentate ligand containing a pyridine functionalized at position 2 with a thione or a thiazol-2-ylidene group and X is either chloro or bromo), were synthesized and their reactivities explored in terms of solvent-dependent ligand substitution, in both the ground and excited states. When they were dissolved in acetonitrile, the complexes bound to the thione ligand underwent reversible ligand exchange with the solvent, resulting in the formation of Re(NCMe)2(CO)3X; the starting complex could be re-formed by precipitation following addition of diethyl ether. On the other hand, the complexes appeared to be inert in dichloromethane or acetone. Conversely, the complex bound to the thiazol-2-ylidene ligand did not display any ligand exchange reaction in the dark but underwent photoactivated ligand substitution on excitation to its lowest metal to ligand charge transfer manifold. Photolysis of this complex in acetonitrile generated multiple products, including Re(I) tricarbonyl and dicarbonyl solvato complexes as well as free thiazol-2-ylidene ligand.

Herein, we report a Rh(II)-catalyzed reaction between 1-tosyl-1,2,3-triazoles and halohydrins to provide 2,6-substituted 3,4-dihydro-2H-1,4-oxazines under basic conditions. The reaction is proposed to undergo a rhodium carbenoid 1,3-insertion into O–H followed by an annulation. The scope includes phenyl or alkenyl C4-substituted triazoles and a range of halohydrins using catalytic Rh2Oct4and K2CO3. A synthesis of the antimicrobial natural product (±)-chelonin C is also reported using this novel methodology.

A series of chiral N-heterocyclic carbene (NHC)-iridium complexes of general formula [(NHC*)Ir(diene)Cl] bearing TFB (tetrafluorobenzobarrelene), TCB (tetrachlorobenzobarrelene), BB (benzobarrelene), and COD (cyclooctadiene) as diene ligands were synthesized and fully characterized. Chiral NHC ligands used were of the type previously reported from our group, with backbone stereocenters as well as axial chirality present. The cationic NHC-iridium complexes [(NHC*)Ir(diene)][PF6] were obtained via chloride abstraction from [(NHC*)Ir(diene)Cl] with AgPF6. X-ray crystallographic data for some of the neutral and cationic complexes were obtained and analyzed. The topographic steric bulk of the chiral NHC ligands was calculated using the SambVca 2.0 program. While attempting to get a single crystal of the unstable (Ra,Ra,S,S)-[(DiPh-2-SICyoctNap)Ir(BB)][PF6] complex, a decomposition product with an unexpected pincer-type NHC*-diene ligand was obtained. The series of chiral cationic NHC-iridium complexes were either isolated or freshly made and used in the representative enantioselective intramolecular hydroamination of N-benzyl-2,2-diphenylpent-4-en-1 amine to produce methylated pyrrolidine product with varying yields and enantioselectivities. More importantly, the catalyst performance of these chiral cationic NHC-iridium complexes was expanded to the enantioselective ring-opening aminations of oxabicycles, where a highly enantioselective catalyst system was identified. Furthermore, we discovered that using the opposite axial stereochemistry on the NHC ligand completely switched the absolute configuration of the product, again showing high optical purity for the enantiomer of the product.

Two previously reported bis-indole alkaloids, echinosulfone A and echinosulfonic acid B, have been isolated for the first time from a Western Australian marine sponge, Crellasp. (order: Poecilosclerida, family: Crellidae). Single-crystal X-ray diffraction of a decomposition product of echinosulfone A prompted our investigation and subsequent structure reassignment of the echinosulfonic acid natural product family, which we report here. The reassignments are supported by analysis of 1D and 2D NMR data, MS fragmentation, and DFT calculations of 13C NMR shifts.

The etiology of fungal pathogenesis of grains is critical to global food security. The large number of orphan biosynthetic gene clusters uncovered in fungal plant pathogen genome sequencing projects suggests that we have a significant knowledge gap about the secondary metabolite repertoires of these pathogens and their roles in plant pathogenesis. Cytochalasans are a family of natural products of significant interest due to their ability to bind to actin and interfere with cellular processes that involved actin polymerization; however, our understanding of their biosynthesis and biological roles remains incomplete. Here, we identified a putative polyketide synthase-nonribosomal peptide synthetase (PKS-NRPS) gene cluster (phm) that was upregulated in the pathogen Parastagonospora nodorumduring its infection on wheat. Overexpression of the transcription factor gene phmRencoded in the phmgene cluster resulted in the production of two leucine-derived cytochalasans, phomacins D and E (1and 2, respectively), and an acetonyl adduct phomacin F. Heterologous expression of the PKS-NRPS gene phmAand the trans-enoyl reductase (ER) gene phmEin Aspergillus nidulansresulted in the production of a novel 2-pyrrolidone precursor prephomacin. Reverse genetics and wheat seedling infection assays showed that ΔphmAmutants exhibited significantly reduced virulence compared to the wild type. We further demonstrated that both 1and 2showed potent actin polymerization-inhibitory activities and exhibited potentially monocot-specific antigerminative activities. The findings from this study have advanced our knowledge based on the biosynthesis and biological roles of cytochalasans, the latter of which could have significant implications for our understanding of the molecular mechanisms of fungus–plant interactions.

Herein we describe the synthesis and isolation of the first low-valent NHC-phosphite nickel complexes of general formula Ni(NHC)[P(OAr)3]2. These three-coordinate Ni(0) compounds were fully characterized, including by X-ray crystallography that highlighted their trigonal planar geometry. The representative complex Ni(IMes)[P(OPh)3]2was used to show that a phosphite ligand is readily substituted in the presence of an aldehyde or nitrile. These stoichiometric studies then led to an investigation of their catalytic properties in the Suzuki–Miyaura cross-coupling reactions between aryl tosylates and aryl boronic acids, a first for such a NHC-Ni catalyst. Finally, mechanistic investigations led to the isolation of a well-defined oxidative addition product.

TFB (tetrafluorobenzobarrelene), TCB (tetrachlorobenzobarrelene), and BB (benzobarrelene) are introduced as alternative diene ligands to COD (1,5-cyclooctadiene) for NHC–iridium complexes of the general formula [(NHC)Ir(diene)Cl]. This new class of compounds was fully characterized, including by X-ray crystallography of appropriate single crystals. The steric requirements of three different NHC ligands as well as the diene ligands were analyzed using the SambVca program. The corresponding cationic and catalytically active [(NHC)Ir(diene)][PF6] complexes were generated via chloride abstraction with AgPF6. Where possible, these species were isolated and fully characterized. The less stable members were freshly made before being tested as catalysts in a prototypical intramolecular hydroamination reaction of an unactivated aminoalkene. A comparison shows how both diene as well as NHC ligands profoundly influence the catalytic activity and point toward future modifications to be made to these catalysts.

Developing molecular circuits that can function as the active components in electrical devices is an ongoing challenge in molecular electronics. It demands mechanical stability of the single-molecule circuit while simultaneously being responsive to external stimuli mimicking the operation of conventional electronic components. Here, we report single-molecule circuits based on spiropyran derivatives that respond electrically to chemical and mechanical stimuli. The merocyanine that results from the protonation/ring-opening of the spiropyran form showed single-molecule diode characteristics, with an average current rectification ratio of 5 at ±1 V, favoring the orientation where the positively charged end of the molecule is attached to the negative terminal of the circuit. Mechanical pulling of a single spiropyran molecule drives a switch to a more conducting merocyanine state. The mechanical switching is enabled by the strong Au–C covalent bonding between the molecule and the electrodes, which allows the tensile force delivered by the STM piezo to break the molecule at its spiropyran C–O bond.

The first approaches to the 10′-anthronyl-2-anthraquinone skeleton have been devised, allowing two syntheses of the marine natural product albopunctatone. Both routes involve regioselective addition of a nucleophilic masked anthraquinone to a protected chrysazin derivative; the best affords albopunctatone in five steps and 35% overall yield. Albopunctatone exhibits potent inhibitory activity against Plasmodium falciparumand negligible toxicity to a range of other microbial pathogens and mammalian cells.

Several trinuclear ferrocenes are obtained by Friedel–Crafts reaction of octamethylferrocene with ferrocenoyl chloride and subsequent modifications. 1,1′-Diferrocenoyloctamethylferrocene (3) is transformed to the divinyl derivative (4a) by reaction with MeLi and AlCl3. The reactive 4acyclizes spontaneously to a [4]ferrocenophane with buta-1,3-diene handle (5) or in the presence of AlCl3to a [3]ferrocenophane with propene handle (6). Structure assignments are supported by X-ray crystallography and NMR spectroscopy, and mechanisms are proposed. Electrochemical behavior of the compounds was investigated with cyclic voltammetry, and assignments of the redox processes were carried out with the aid of density functional theory calculations. The synthesized compounds and demonstrated transformations represent useful tools for preparation of materials for charge-transport studies in metal−molecule−metal junctions.

A novel chiral disulfoxide ligand pair bearing fluorine atoms at the 6 and 6′ position of its atropisomeric backbone, (M,S,S)- and (P,S,S)-p-Tol-6F-BIPHESO, was synthesized. Complexation to a rhodium(I) precursor gave rise to μ-Cl- and μ-OH-bridged rhodium dimer complexes incorporating the new (M,S,S)-p-Tol-6F-BIPHESO ligand, while its sibling (P,S,S)-p-Tol-6F-BIPHESO was not complexed efficiently to the rhodium precursor. The performance of this disulfoxide ligand [(M,S,S)-p-Tol-6F-BIPHESO] in catalysis was tested in both 1,4- and 1,2-addition reactions of arylboronic acids. We show that addition to both cyclic and acyclic enones as well as N-tosylarylimines proceeds with high yields and high enantioselectivities to give the corresponding products. The synthesis of enantiomerically pure p-Tol-6F-BIPHESO is straightforward and inexpensive which, together with the high catalytic performance and wide substrate scope for these addition reactions, makes it a very attractive alternative to more classical chiral ligand entities.

The reaction of the β-triketonate ligands tris(4-methylbenzoyl)methanide and tribenzoylmethanide with the trivalent lanthanoids Eu3+, Er3+, and Yb3+in the presence of Cs+afforded polymeric structures where the repeating units are represented by bimetallic tetranuclear assemblies of formulation {[Ln(Cs)(β-triketonate)4]2}n. The only exception is the structure formed by the reaction of tris(4-methylbenzoyl)methanide, Yb3+, and Cs+, which yielded a polymeric assembly where the repeating units are mononuclear Yb3+complexes bridged by Cs+cations. Photophysical measurements on the obtained materials confirmed efficient sensitization from the ligand excited states to the 4f* excited states of the three lanthanoids. According to transient absorption data, Er3+and Yb3+are sensitized via energy transfer from the triplet state of the β-triketonate ligands. On the other hand, energy transfer to Eu3+seems to occur via an alternative pathway, possibly directly via the singlet state or through ligand to metal charge transfer states. The emission measurements confirm efficient sensitization for all three lanthanoids and bright near-infrared emission for Er3+and Yb3+, a characteristic that seems to be linked to the specific chemical structure of the β-triketonate ligands.

This paper describes the syntheses of several functionalized dihydropyrene (DHP) molecular switches with different substitution patterns. Regioselective nucleophilic alkylation of a 5-substituted dimethyl isophthalate allowed the development of a workable synthetic protocol for the preparation of 2,7-alkyne-functionalized DHPs. Synthesis of DHPs with surface-anchoring groups in the 2,7- and 4,9-positions is described. The molecular structures of several intermediates and DHPs were elucidated by X-ray single-crystal diffraction. Molecular properties and switching capabilities of both types of DHPs were assessed by light irradiation experiments, spectroelectrochemistry, and cyclic voltammetry. Spectroelectrochemistry, in combination with density functional theory (DFT) calculations, shows reversible electrochemical switching from the DHP forms to the cyclophanediene (CPD) forms. Charge-transport behavior was assessed in single-molecule scanning tunneling microscope (STM) break junctions, combined with density functional theory-based quantum transport calculations. All DHPs with surface-contacting groups form stable molecular junctions. Experiments show that the molecular conductance depends on the substitution pattern of the DHP motif. The conductance was found to decrease with increasing applied bias.

Diorganotin(IV) derivatives of 4‐acyl‐5‐pyrazolones Q2SnR2[HQ = 3‐methyl‐1‐phenyl‐4‐R‐5‐pyrazolone: HQnPe, R = neopentylcarbonyl; HQiPr, R = isopropylcarbonyl; HQtBu, R = tert‐butylcarbonyl; HQCy, R = cyclohexylcarbonyl; HQCp, R = cyclopentylcarbonyl; HQEtCp, R = (ethylcyclopentyl)carbonyl] have been synthesized and characterized spectroscopically (IR, far‐IR, 1H, 13C and 119Sn NMR) and structurally (X‐ray). Steric bulkiness in the acyl fragment of HQtBuinduces partial dissociation in solution of (QtBu)2SnMe2, which exists as an equilibrium mixture of six‐ and five‐coordinate tin species. Single‐crystal X‐ray structure determinations of several representative complexes are presented. Whereas the dialkyltin(IV) complexes are always trans‐octahedral, a diphenyltin(IV) derivative exists in the solid state that has the two phenyl groups in a cisarrangement. DMol3 and CASTEP DFT studies of this unprecedented cis, and the corresponding transconfigurations, show the former to be slightly more stable, in agreement with the diffraction study. Solid‐state 119Sn cross‐polarization magic‐angle spinning NMR spectroscopic data show that the isotropic chemical shifts (δiso,mas) and chemical‐shift anisotropies/spans (Δδ/Ω) that characterize the diphenyl(IV) derivatives are markedly removed from values measured for the corresponding dimethyl and di‐n‐butyl derivatives, thereby adding further evidence for a stable cisconfiguration in the diphenyl(IV) systems. This is supported by GIPAW DFT calculation of the 119Sn isotropic shifts and chemical‐shift anisotropies/spans from fully relaxed structures by using the CASTEP code, which provides a direct link between the cisdiphenyl(IV) arrangement and the reported differences in the 119Sn NMR spectroscopic parameters.

Addition of 1‐alkyl‐3‐methylimidazolium (Cn‐mim) cations 3–5to a mixture of bis‐phosphonium cation 2and sodium p‐sulfonatocalix[4]arene (1) in the presence of lanthanide ions results in the selective binding of an imidazolium cation into the cavity of the calixarene. The result is a multi‐layered solid material with an inherently flexible interplay of the components. Incorporating ethyl‐, n‐butyl‐ or n‐hexyl‐mim cations into the multi‐layers results in significant perturbation of the structure, the most striking effect is the tilting of the plane of the bowl‐shaped calixarene relative to the plane of the multi‐layer, with tilt angles of 7.2, 28.9 and 65.5°, respectively. The lanthanide ions facilitate complexation, but are not incorporated into the structures and, in all cases, the calixarene takes on a 5− charge, with one of the lower‐rim phenolic groups deprotonated. ROESY NMR experiments and other 1H NMR spectroscopy studies establish the formation of 1:1 supermolecules of Cn‐mim and calixarene, regardless of the ratio of the two components, and indicate that the supermolecules undergo rapid exchange on the NMR spectroscopy timescale.

Extension of previous work on the lanthanideIII ion complexes of ptertbutyltetrathiacalix[4]arene has led to a variety of structurally characterised species containing oxo, hydroxo and aqualigands presumably derived from water present in the preparative medium, along with the thiacalixarene in various stages of deprotonation. The overall stoichiometry of some species is remarkably complicated due to the presence of simple anions and multiple solvents. Simplest is the binuclear complex [μH2OLnOdmf22HL·dmf2]·nS dmf = dimethylformamide [1Ln, Ln = Sm nS = 2dmf, Eu nS = 1.5dmf·2MeCN], also the bestdefined of all the arrays studied. The heaviest lanthanides give trinuclear LnOH3·2LnLH·xdmf·yH2O 2Ln, Ln = Yb, Lu, while both oxo and hydroxo species are isolable with Eu: trinuclear Eu3OLLHLH4·13dmf 3 and tetranuclear Eu4OOH2LLH22LH4·12dmf 9, both somewhat atypical species containing uncoordinated thiacalixarene molecules within the lattice. Anion NO3, ClO4 coordination, as in the tri and tetranuclear species, 4–6Ln, 9, 10Ln, 11Ln, 12, seems especially favoured for the lighter lanthanides. In these arrays, the Ln3and Ln4aggregates are triangular or quasisquareplanar, except for Gd4O2LH24·2H2O·2MeOH·2dmf·3.375CH2Cl212, where there is a Zdisposition. Most common is an Ln3O core, which spans the gamut of Ln in three sets of crystal forms with cells of similar dimensions: for Ln = La...Nd, Ln3OHNO34LH22·4.5dmf 5Ln space group C2m, and Sm...Lu, Ln3ONO3LH2·4H2O·2dmso·2MeCN·3py 6Ln space group P21n, conformity with crystallographic symmetryentails disorder of the Ln atoms; in a further form of lowersymmetry Pn, pyHLn3ONO32LH2·2MeCN·xH2O·ydmso·1.5py·MeOH 7Ln, Ln = La, Ce, with no imposed crystallographic symmetry, some disorder persists, but none is found in the crystallographically unrelated form of 8Pr, Pr3ONO3LH2·16H2O·2MeCN·5py. Ln4OHNO33L2·8dmf·2dmso·3H2O 10Ln, Ln = Pr...Gd, previously defined for Nd has a squareplanar Ln4O array sandwiched between a pair of L ligands, with a similar form found for Ln4OClO42L2·xdmf·yH2O 11Ln, Ln = La...Nd.

The 1:1 tribenzylphosphane PBn3 complexes of goldI[Bn3PAuX] X = Cl and Br have been synthesised, and their structures were determined by singlecrystal Xray crystallography. The compounds are isomorphous, neutral molecules with linearly coordinated P–Au–X arrays. Each structure contains three independent [Bn3PAuX] entities lying on the three threefold axes of space group P3c1. The mean bond lengths are Au–Cl 2.3028, Au–P 2.22711 Å for the chloride and Au–Br 2.40410, Au–P 2.2294 Å for the bromide. These contrast with the 1:1 adducts previously reported for copperI, which take the form [CuPBn32][CuX2]. The 1:2 AuX:PBn3compounds that have been synthesised are formulated as [AuPBn32]X·nH2O X = Cl, n= 1 or 2; X = I and BF4, n= 0. Singlecrystal Xray structures show that linearly twocoordinate centrosymmetric [AuPBn32]+arrays are found in [AuPBn32]Cl·H2O and [AuPBn32]BF4with Au–P bond lengths of 2.29887 and 2.30167 Å for the chloride and 2.29757 Å for the tetrafluoroborate. νAuX bands in the farIR spectra of [Bn3PAuX] are assigned at 320 and 227 cm–1for X = Cl and X = Br, respectively. The 31P CP MAS NMR spectra of [Bn3PAuX] X = Cl, Br and [AuPBn32]X X = Cl·H2O, Cl·2H2O, I, BF4 are reported, and the observation of 2JPP coupling in the spectrum of [AuPBn32]Cl·2H2O is consistent with the presence in this complex of noncentrosymmetric cations in which the two phosphorus atoms are inequivalent.

After vacuum dehydration, a number of hydrated trivalent lanthanoid trifluoromethanesulfonates (“triflate”, “OTf” = F3CSO3), when recrystallized from various alcohol (ROH) solutions, yield solvates Ln(OTf)3·xROH, x= 3, 5 or 6. The following have been defined crystallographically (R/Ln/x): Me/La/3;Me/Gd/6; Et/Sm/3; Et/Gd/5 iPr/Nd,Sm/3. The Me/Gd/6complex, Gd(OTf)3·6MeOH is a mononuclear/ionic form [(MeOH)6Gd(O–OTf)2](OTf), the gadolinium environment being octacoordinate, square‐antiprismatic with the O–OTf donors quasi‐trans on different faces of the coordination polyhedron; the Et/Gd/5 complex is neutral, molecular, mononuclear [(EtOH)5Gd(O–OTf)3], also with an octacoordinate, square‐antiprismatic coordination sphere, derivative of that of the methanol solvate. The remainder form one‐dimensional polymeric arrays, successive lanthanoid atoms linked by (μ‐O–OTf–O′)3triads, at either end of a tricapped trigonal prismatic array, the ROH molecules contributing the capping atoms. A (“baseline”) (re‐)determination of the “parent” Sm(OTf)3·9H2O is also recorded.

The water‐soluble calix[4]arene bearing p‐substituted phosphonic acid groups is accessible in five steps in overall 62 % yield, with the hydrogen‐bonding prowess of the acidic groups dominating its self‐assembly processes. These include the formation of 3.0(3) nm and 20(2) nm nanorafts of the calixarene in water using spinning disc processing, stabilized by acetonitrile, and nanorafts in the gas phase (≤20 molecules). The 20(2) nm particles transform into 3.0(3) nm particles prior to crystallization into a compact bilayer, whereas crystallization in the presence of large organic molecules gives an expanded bilayer interposed by layers of water molecules.

In toluene fullerene C70forms 2:1 complexes with p‐benzylcalix[5]arene (1) and p‐phenylcalix[5]arene (2), [C70⊂12]⋅6 (C7H8) and [C70⊂22]⋅7 (C7H8). The fullerene molecules are completely shrouded by two calix[5]arenes in addition to terminal benzyl groups from other supermolecules, [C70⊂12], and solvent. Within the capsule‐like supermolecules the calixarenes have distinctly different arrangements relative to the principal axis of the fullerene; for [C70⊂12]⋅6 (C7H8) the oxygen planes of the two calixarenes are skewed by 37.0 and 47.5°, whereas in [C70⊂22]⋅7 (C7H8) the principal axes of the fullerene and the two encapsulating calixarenes are more closely aligned with the corresponding angles at 9.7 and 8.6°, and features a pentaphenyl inter‐calixarene embrace. The Hirshfeld surfaces of these two complexes have been investigated for a detailed understanding of the orientation and nature of interactions of C70with the cavitand‐type molecules and toluene.

p-But-calix[5]arene forms crystalline inclusion complexes with o- and m-carboranes in toluene or dichloromethane–hexane, but not with the p-isomer, the extended structures being based on 1 : 1 host–guest supermolecules, with the p-But-substituents creating a snug fit for o- and m-carborane; p-carborane forms a highly hexane soluble complex, induced by grinding, which crystallizes as fibres. Solution phase studies showed the presence of a 1 : 1 host–guest stoichiometry with all three isomeric carboranes as determined from Job plots. The association constants for the o- and m-carborane complexes are 6.4 ± 0.3 M−1 and 3.8 ± 0.1 M−1 respectively, whereas the p-isomer is only weakly associated. Competition experiments involving all three isomers show rapid exchange on the NMR time scale, and no selectivity in solution is evident. Selective association involving the o- and m-isomers in the solid state is therefore remarkable, and it is a manifestation of crystal packing forces which embodies the differences in dipole moments of the carboranes.

Pristine fullerene C60 has a fcc structure. Crystallisation of the fullerene in a variety of solvents can lead to inclusion complexes, as well as discrete host–guest complexes in the presence of cavitands and porphyrins, and related molecules. The complexes retain varying degrees of fullerene···fullerene interactions at the van der Waals limit, except in a limited number of cases where the fullerenes are completely shrouded by one or more included/host molecule. Analysis of the fullerene···fullerene interactions in these complexes reveals a diverse structural arrangement of the fullerenes. They can be organised into dimers, single linear columns or zigzag chains, double columns, spectacular fivefold Z-shaped columnar arrays, hexagonal close-packed layers, corrugated sheets, honeycomb motifs, non-close-packed layers and complex three-dimensional networks. Disorder of the fullerenes in the solid state is common, although structures with close-packed planar arrangements of C60 molecules and/or with symmetry matching between the host molecule and the fullerene (two-, three- and fivefold symmetry) tend to have less disorder of the fullerene. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2006)

For the first time the utility of p-sulfonatocalix[8]arene to form a chalice-like cavity for the solid state inclusion of a classical coordination complex [Co(phen)3]3has been demonstrated. In the presence of Yb3ions, a new crystalline material is formed which possesses large diameter, negatively charged channels which propagate through the material in three dimensions.

A new paradigm for the synthesis of 4′-pyridyl terpyridines using polyethyleneglycol (PEG) as a benign reaction medium is described, with the compounds readily accessible in high purity in ca.4 hours using a ‘one pot’ procedure. This method requires no product purification and affords the desired compounds in reasonable yield without the formation of unwanted side products.

An extensive accurate X-ray data set for diaqua(glycylglycinato)copper(ii) hydrate, Cu(glygly)(OH₂)₂·H₂O, at 10 K is reported. The molecular structure is very accurately defined. The Cu(glygly)(OH₂)₂ unit approximates to a square pyramid with the apical water molecule only loosely bound. The data have been analysed by multipole and valence orbital population models and the topology of the electron density has been examined for chemical bonding features. There are two independent molecules of the complex in the unit cell, and the agreement between their bonding features is used as a measure of the validity of obtaining quantitative valence-related parameters from X-ray data. The agreement is quite reasonable. Atomic charges evaluated by the Stockholder and monopole population methods do not conform with chemical expectations. Those from the sum of valence orbital populations and the atom-in-molecules approach are more reasonable but contain anomalies. The ‘hole’ in the 3d10 shell corresponding to the 3d9 configuration, predicted on the grounds of ligand field theory, is seen as a much lowered (1.16 e) population of 3d_z2 relative to the other 3d orbitals (av. 1.65 e). Populations of valence hybrid orbitals conform with chemical expectations and, for the (sp2)_σ hybridised carbon atoms of C&z.dbd;O groups, relocation of electrons from a p_π orbital to those σ hybrids is seen. Bond critical points have been located between all the appropriate non-hydrogen atom pairs. The electron densities at these points show values typical for mixed ionic/covalent character in the Cu–O and Cu–N interactions and of covalent character in the C–C, O–C and N–C bonds. The Laplacian of the density at the bond critical points also behaves in a fashion which conforms with those bond types, although the scatter in the results is greater. There is little evidence of the copper atom having influenced the electron densities of the bonds between light atoms within the glycylglycinato moiety.

The crystal structures of the α‐alums rubidium chromium bis(­sulfate) dodecahydrate, RbCr(SO4)2·12H2O, and caesium chromium bis[tetraoxoselenate(VI)] dodecahydrate, CsCr(SeO4)2·12H2O, have been determined by X‐ray diffraction at 293 and 12 K. The metal atoms lie on sites and the anions lie on threefold rotation axes. The accurate and extensive data sets lead to much more precise determinations than are available from earlier work, particularly at 12 K. The changes in the atomic displacement parameters between 293 and 12 K correspond to the respective predominances of intermolecular and intramolecular vibrational effects.

The novel 2,7-bis((TIPS)ethynyl)-10b,10c-diethyldihydropyrene photochrome (TIPS = triisopropylsilyl) was observed to undergo thermal rearrangement to 2,7-bis(TIPS-ethynyl)-pyrene in the solid state. The transformation proceeds stepwise with ethyl groups “dancing” out of the dihydropyrene core toward the periphery of the polycyclic framework. The formation of two regioisomers occurs initially and is followed by two progressive de-ethylations to give a pyrene. This transformation occurs in the solid crystalline state and represents a unique example of a single-crystal-to-single-crystal (SC-SC) transformation involving C–C bond cleavages with hydrocarbon fragments escaping the ordered crystalline structure. Detailed characterizations of the transformation by in situ temperature-dependent X-ray single-crystal diffraction supported by thermal analysis, HPLC-mass spectrometry experiments, NMR spectroscopy, and theoretical calculations, are reported.

In the presence of lanthanide ions, a Coiii sepulchrate cation CodiHOsar3and sodium p-sulfonatocalix4arene form a 1 1 host–guest complex which is self-assembled into a zeolite-like lattice network comprised of parallel, single stranded helices.

In the presence of tetraphenylphosphonium and aquated ytterbium(iii) ions, conformationally flexible p-sulfonato-calix[8]arene forms an extended structure with two dimensional porosity involving the assembly of phosphonium cations and ‘molecular capsules’ comprised of two calixarenes shrouding three phosphonium cations.

p-Phenylcalix[4]arene is formed directly from p-phenylphenol in 66% yield (50% isolated yield) using poly(ethylene glycol) as the reaction medium, with crystallization of the pure cavitand from toluene mediated by p-carborane. The solid-state structure comprises interlocking columnar arrays.

p-Phenylcalix[4]arene is formed directly from p-phenylphenol in 66% yield (50% isolated yield) using poly(ethylene glycol) as the reaction medium, with crystallization of the pure cavitand from toluene mediated by p-carborane. The solid-state structure comprises interlocking columnar arrays.

Reaction of equimolar amounts of sodium para-sulfonato-calix4arene, tetraphenylphosphonium chloride and ytterbium chloride in water results in the formation of a mineral clay-like structure, where the hydrophobic tetraphenylphosphonium cations interpose a bilayer arrangement based on a 2D coordination polymer of calix4arene5−NaYb3.

p-Sulfonatocalix6arene in the double cone conformation forms a molecular capsule-like arrangement confining two tetraphenylphosphonium cations, as part of an extended structure involving layers of additional tetraphenylphosphonium cations, aquated lanthanide ions and a large array of water molecules.

The crystal structure of the title compound, [ReCl4(C8H10N2)2], has been determined by X‐ray diffraction at 11 K and by neutron diffraction at 20 K. The accurate and extensive data sets lead to more precise determinations than are available from earlier work. The agreement in atomic positional and displacement parameters at these very low temperatures is good. The results will facilitate re‐examination of the magnetic structure of the complex. The Re atom lies on a special position and the molecule has twofold crystallographic symmetry.

Precise X‐ray determinations of the crystal structure of the 1:2 complex of N‐ethyl‐N‐methyl­morpholinium and 7,7,8,8‐tetra­cyano‐p‐quinodi­methanide, abbreviated as MEM–TCNQ or MEM(TCNQ)2(C7H16NO+·2C12H4N40.5−), have been performed at 293 and at 10 K. Evidence for the expected spin‐Peierls transition at 19 K is not found, and this may follow from radiation damage to the crystal or from insufficient equipment sensitivity.

The crystal structure of Na2Fe(CN)5(NO)·2D2O, disodium penta­cyano­nitro­syl­ferrate(III) bis­(dideuterium oxide), has been determined by X‐ray diffraction at 11 and 293 K, and by neutron diffraction at 15 K. The accurate and extensive data sets lead to more precise determinations than are available from earlier work. The agreement in atomic positional and displacement parameters between the determinations at low temperature is very good.

The crystal structure of dicaesium potassium hexacyanomanganese(III) has been determined by X‐ray diffraction at 293, 85 and 10 K. The Mn and K atoms lie on inversion centres and the Cs atom is in a general position. The accurate and extensive data sets collected should be suitable for charge–density analysis studies.

Phenyl embraces involving tetraphenylphosphonium cations feature in complexes of p-sulfonatocalix4arene where a phenyl ring of a cation is included in the cavity of the calixarene. The overall structures are based on pseudo-polymorphic supramolecular arrays and their formation is templated or induced by lanthanide ions.

Phenyl embraces involving tetraphenylphosphonium cations feature in complexes of p-sulfonatocalix[4]arene where a phenyl ring of a cation is included in the cavity of the calixarene. The overall structures are based on pseudo-polymorphic supramolecular arrays and their formation is templated or induced by lanthanide ions.

The crystal structure of trisodium hexanitro­cobaltate(III) has been determined by X‐ray diffraction at 293 and 10 K. It contains the slightly distorted octahedral Co(NO2)63−anion.

The title compound, (NH4)ZnPO4–HEX, is built up from a three‐dimensional network of ZnO4and PO4tetrahedra [dav(Zn—O) = 1.9400 (7) Å and dav(P—O) = 1.5396 (7) Å], fused together viaZn—O—P links [θav= 133.47 (4)°]. An undisordered linear Zn—O—P bond occurs (all three atoms lie on a threefold axis). Extra‐framework NH4+cations, which interact with the [ZnPO4]−framework by hydrogen bonds, complete the crystal structure.

The crystal structure of tricaesium cobalt pentachloride has been determined by X‐ray diffraction at 10 K. The Co atom is at a site with symmetry, one Cs atom is at a site with 42 symmetry, the other has mmsite symmetry, one Cl ligand has 4/msymmetry and the other has msymmetry. The accurate and extensive data set collected should be suitable for charge–density analysis studies. In the CoCl42−ion, as the temperature is lowered, the Co—Cl bond length increases a little and the small distortion of the tetrahedron (site symmetry 2m) is slightly reduced.

The crystal structure of tripotassium sodium hexa­chloro­ferrate(II) has been determined by X‐ray diffraction at 293, 84 and 9.5 K. The accurate and extensive data sets collected should be suitable for charge–density analysis studies.

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.