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Calix[n]arenes – are easily accessible three-dimensional macrocyclic compounds. Modified calix[n]arenes capable with high selectivity recognize, bind in supramolecular complexes and separate substrates of similar properties such as cations, anions, gases, neutral organic molecules, and biomolecules. This review summarizes data on application as radionuclide extractants and sorbents, sensitive layer of chemosensors, porous materials for gases sorption, chromatography phases for (chiral) separation, stereoselective catalysts of organic reactions, resist for nanolithography, selective modulators of ATP-dependent pumps in smooth muscle cells, inhibitors of therapeutically important enzymes, vectors for gene transfection, fluorescent markers for cell imaging and “molecular glue” for protein crystallization of the functional calixarenes. Special attention in the paper is addressed to the application of the phosphorus-containing calixarenes in radiochemistry, chiral catalysis and bio-medicine.

On the way to copper(I) iodide coordination polymers with specific luminescent properties, the in situ reduction of Cu(II) in the presence of KI and bidentate N-heteroatomic ligand, either pyrazine (pyz) or 4,4′-bipyridine (bpy), resulted in one two-dimensional and two three-dimensional new coordination networks. Starting from Cu(NO3)2·3H2O in the presence of pyz, successive precipitation of known yellow [(CuII)2(pyz)]n, new orange [CuII(pyz)]n, and new dark blue {[CuI(pyz)2]·I5}npolymeric solids was observed. Starting from the same salt in the presence of bpy resulted in the successive precipitation of known yellow [(CuII)2(bpy)]nand new brown {[CuII(NO3)(bpy)2]·I3·(dmf·H2O)}ncoordination polymers. By using either Cu(CH3COO)2·H2O or Cu(BF4)2as starting materials, both known forms, yellow [(CuII)2(bpy)]nand orange [CuII(bpy)]n, precipitated successively. The new solids were characterized by IR spectroscopy and X-ray analysis. [CuII(pyz)]nrepresents the missing member in the row of two-dimensional coordination networks with general formula [CuIX(pyz)]n(X = Cl, Br, I). Its steady state and time-resolved characterization together with DFT and TDDFT calculations revealed that the emission at room temperature is mainly delayed fluorescence originating from mixed singlet metal-to-ligand charge transfer and halide-to-ligand charge transfer states, while that at 77 K is phosphorescence, associated with the small singlet–triplet energy differences (ΔE= 70 meV).

We report on investigations of reactions of tBu2Zn with 8‐hydroxyquinoline (q‐H) and the influence of water on the composition and structure of the final product. A new synthetic approach to photoluminescent zinc complexes with quinolinate ligands was developed that allowed the isolation of a series of structurally diverse and novel alkylzinc 8‐hydroxyquinolate complexes: the trinuclear alkylzinc aggregate [tBuZn(q)]3(13), the pentanuclear oxo cluster [(tBu)3Zn5(μ4‐O)(q)5] (2), and the tetranuclear hydroxo cluster [Zn(q)2]2[tBuZn(OH)]2(3). All compounds were characterized in solution by 1H NMR, IR, UV/Vis, and photoluminescence (PL) spectroscopy, and in the solid state by X‐ray diffraction, TGA, and PL studies. Density functional theory calculations were also carried out for these new ZnIIcomplexes to rationalize their luminescence behavior. A detailed analysis of the supramolecular structures of 2and 3shows that the unique shape of the corresponding single molecules leads to the formation of extended 3D networks with 1D open channels. Varying the stoichiometry, shape, and supramolecular structure of the resulting complexes leads to changes in their spectroscopic properties. The close‐packed crystal structure of 13shows a redshifted emission maximum in comparison to the porous crystal structure of 2and the THF‐solvated structure of 3.

In this work, the enantioseparation of 15 structurally similar chiral solutes is studied, and analysis of the retention factors is performed using a genetic algorithm and multiple linear regression analysis technique. The present quantitative structure–enantioselective retention relationship model generated for retention factors' data has confirmed the importance of a number of descriptors altering the retention behavior and enantioselectivity of the studied compounds. Thus, fragment‐based descriptor PSA, which encodes polar surface area, has confirmed the crucial role of heteroatoms in the retention behavior exhibited by pyrroliddin‐2‐ones. The presence of ELUMOdescriptor, which represents a quantum‐chemical property, has indicated the role of charge transfer interactions between the chiral stationary phase and enantiomers to retention factors, showing that lowest unoccupied molecular orbital energy is significantly different between enantiomers. The developed model exhibits a very good performance characterized by following statistical parameters: r2= 0.93 for training set and r2= 0.99 for the validation set. The selected three‐variable model displays high predictive ability, catching the main factors affecting the enantioselectivity of studied chiral compounds, and therefore can be used for prediction of retention factors of other chiral compounds of similar structure to improve the separation process and so on. Chirality, 2011. © 2011 Wiley Periodicals, Inc.

Zinc links: Solid‐state desolvation of the dimeric alkoxide [{tBuZn(μ‐OtBu)(thf)}2] leads to a trimer [{tBuZnOtBu}3] with a unique core structure; subsequent grinding affords the tetrameric cubane [{tBuZnOtBu}4]. This approach demonstrates a new direction in the generation of metal alkoxide clusters.

Schritt für Schritt zum Cluster: Die Festkörperdesolvatisierung des dimeren Alkoxids [{tBuZn(μ‐OtBu)(thf)}2] führt zum trimeren [{tBuZnOtBu}3] mit einzigartiger Kernstruktur. Anschließendes Zermahlen ergibt das tetramere Cuban [{tBuZnOtBu}4]. Dieses Ergebnis zeigt einen neuen Ansatz für die Herstellung von Metallalkoxidclustern auf.

Pores for thought: Dinuclear aluminum–cinchone complexes are used to construct chiral architectures through noncovalent‐interaction‐driven self‐assembly (see picture). The flexible desolvated material with ultramicropores is a selective adsorbent with unique properties, such as temperature‐triggered adsorption of N2and high affinities for H2, CO2, and CH4.

Smarte Poren: Zweikernige Aluminium‐Cinchonin‐Komplexe dienen als Bausteine zur Selbstorganisation chiraler Architekturen mit nichtkovalenten Wechselwirkungen (siehe Bild). Das flexible desolvatisierte Material mit Ultramikroporen ist ein selektives Adsorptionsmittel mit einzigartigen Eigenschaften, z. B. hohen Affinitäten für H2, CO2und CH4und einer temperaturgeregelten Adsorption von N2.

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The synthesis and characterization of six new spin-crossover (SCO) materials FeLDx(NCX)2(1:? X S, x1; 2:? X Se, x1; 3:? X S, x2; 4:? X Se, x2; 5:? X S, x3; 6:? X S, x4) are reported, where LD1-LD4stand for the dissymmetrical tetradentate ligands obtained by 1:1:1 Schiff base condensation of 1,3-diaminopropane (LD1, LD3) or 2,2-dimethyl-1,3-diaminopropane (LD2, LD4), 2-acetylpyridine (LD1, LD2) or 6-bromo-2-acetylpyridine (LD3, LD4), and 5-methylimidazole-4-carboxaldehyde. Magnetic and Mössbauer studies and X-ray structures at 100, 200, and 300 K (low-spin (LS) state) and 350 and 400 K (high-spin (HS) state) for 3, and 180 K (HS state) for 6revealed the occurrence of unusual SCO behaviors:? complex 3undergoes a first-order SCO centered at 315 K with a 4 K wide hysteresis associated with an order-disorder phenomenon for the propylene fragment of LD2, whereas 1exhibits a two-step SCO occurring at ~202 (smooth) and 297.5 K (11 K wide hysteresis). A significant mass effect is induced upon changing the thiocyanate for selenocyanate ligands:? the SCO of 4(NCSe) occurs ~100 K higher than for 3. These new features are discussed comparatively to the results obtained for a related series of SCO materials. 5and 6, which include a 6-bromopyridyl substituent, remain HS over the whole 80-300 K range.

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Chiral calix[4]arene α-aminophosphonic acids were obtained through diastereoselective Pudovik-type addition of sodium ethyl phosphites to the chiral calixarene imines, removal of chiral auxiliary groups, and mild dealkylation of phosphonate fragments. The diacids obtained show inhibitory activity toward porcine kidney alkaline phosphatase that depends considerably on the absolute configuration of the α-carbon atoms.

The X-ray structure analysis of the alkylaluminum and-indium compounds derived from methyl thiosalicylate,Me2Al(SC6H4-2-CO2Me) and [Me2In(μ-SC6H4-2-CO2Me)]2, revealed that the intermolecular S···C(π) interaction between the Al–S thiolate units and the ester π-surface can effectively compete with the hypercoordinate sulfur–metal dative bond. The former compound exists as the noncovalently bonded dimer involving the thiolate sulfur atom and the electrophilic carbon atom of the ester functionality, whereas the indium complex is a five-coordinate dimer with the In2(μ-S)2 central core. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2005)

The Cambridge Structural Database showed in mid 2002 about 20.000 structures containing halogen atoms and aryl rests with distances d between the aryl center and the halogen atom, which would allow both hydrogen bonds with the aromatic hydrogens and/or van der Waalsinteractions with the π-cloud. The latter are characterized by short distances d and by small angles α between the vector along the aryl centroid–halogen line and the perpendicular vector originating in the aryl center (the plane normal). The cases with d < 3.0 Å for F; and d < 3.5 Å for Cl, Br or I (outliers neglected), and α ≈ 10 ± 5°, indicating predominating van der Waals forces, amount to several hundreds. The majority of fragments exhibit larger d and α values, in line with avoidance of electrostatic repulsion between the negative partial charges of the halogens and the π-cloud center, and with an increasing electrostatic attraction with the aromatic hydrogen atoms. The corresponding hydrogen bonds are characterized by longer distances d and by angle values of α > 60° (about 40 % of the fragments), with only very few cases close to linear hydrogen bonds (then with α = 90°). Compounds containing metal–halogen bonds were omitted in view of possible strong orientational interferences. The structures were screened with four different halogen binding modes, all of them containing the halogen attached to a carbon atom, but with different hybrizations at the connecting carbon centers. The results show only small differences in the distance distributions, with a slight preference for smaller α values for sp2 frameworks. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2005)

Summary:The isolation and structural characterization of a methylaluminium(bisphenoxide)‐ε‐caprolactone complex is reported. While the three‐coordinate methylaluminium complex was found not to catalyze the polymerization of ε‐caprolactone, its oxygenation led to the formation of an aluminium methoxide compound, which appeared to be a very good initiator. The relative propensity of the AlX bonds for monomer insertion in the initial step of polymerization is also discussed.

Two new heterobinuclear complexes, [(bipy)(C2O4)Cr(μ-C2O4)Cu(Hfsaaep)(H2O)]·2H2O (1) and [(phen)(C2O4)Cr(μ-C2O4)Mn(phen)2(N3)]·H2O (2) have been obtained by using bis(oxalato)chromium(III) anions, [Cr(AA)(C2O4)2]−, as building blocks [AA = 2,2′-bipyridine (bipy); 1,10-phenanthroline (phen)]. The crystal structures of the two complexes have been solved. These complexes comprise neutral oxalato-bridged CrIII−CuII and CrIII−MnII units. The [Cr(AA)(C2O4)2]− anion acts as a bidentate ligand toward CuII in compound 1 and as a monodentate ligand toward MnII in compound 2. The copper(II) ion in 1 exhibits a slightly distorted square bipyramidal stereochemistry, with the aqua ligand and one of the bridging oxalato oxygen atoms disposed in the apical positions [Cu(1)−O(1w) = 2.360(3) Å and Cu(1)−O(4) = 2.504(2) Å]. The second bridging oxalato oxygen atom [Cu(1)−O(2) = 2.0747(18) Å] and the N,N,O-type Hfsaaep ligand are located in the basal plane. The distance between the CrIII and CuII ions across the bridging oxalate unit is 5.506 Å. The MnII ion in compound 2 is hexacoordinate (two chelating phen ligands, one oxalato bridging oxygen, and one terminal azido group). The intermolecular CrIII···MnII distance is 5.257 Å. The magnetic properties of the two complexes have been investigated. The magnetic coupling between CrIII and CuII in 1 was found to be ferromagnetic (J = +1.4 cm−1). The nature of the ground state (S = 2) has been further confirmed by plotting the magnetization-versus-field curve. An antiferromagnetic interaction was found between CrIII and MnII in compound 2 (J = −1.9 cm−1). The magnetization-versus-field curve indicates the occurrence of a crossover between the Zeeman components: MS = −1 (ground state S = 1), MS = −2, from the first excited state (S = 2), and MS = −3, from the second excited state. The EPR spectra of the two compounds are discussed. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2004)

Until now, the known structures of heterodinuclear Cu−Ln complexes involve compartmental Schiff-base ligands with saturated diamino chains. We report here two Cu−Ln complexes (Ln = Gd or Ce) which are the first structurally characterized Cu−Ln entities involving S-methylisothiosemicarbazide as the diamino bridge, with open chain and macrocyclic ligands. The macrocyclic Cu−Gd entity is a well isolated dinuclear complex whereas two hydrogen bonds join together a pair of binuclear Cu−Ce complexes to give tetranuclear {Cu−Ce···Ce−Cu} entities. The Cu−Gd complexes [H = -J(SCuSGd)] exhibit ferromagnetic interactions between 5 and 5.5 cm⁻¹. Since the Cu−Ce complexes do not follow the Curie law due to the presence of orbital degeneracy, an analysis based on a simple spin-only Hamiltonian is not possible. Nevertheless, the EPR spectra of the Cu−Ce complexes do confirm the existence of magnetic interactions. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2004)

The reaction of Et3B with one equivalent of N-substituted salicylideneimine HsaldR′ yields the monomeric O,N-chelate complexes Et2BsaldR′, where R′ Me 1 or Ph 2. The crystal structure of the resulting complexes has been determined by X-ray crystallography. The molecular structure of these complexes consists of monomeric four-coordinate chelates and their primary arrangement in the crystal structure is determined by the C–HOaryloxidehydrogen bonds. An extended crystal structure analysis reveals that the adjacent monomeric moieties of 1are interconnected by C–HiminoO hydrogen bridges resulting in a 1-D motif infinite H-bonded chain, whereas the crystalline complex 2comprises dimeric molecules linked through a pair of intermolecular C–HaromO interactions. The supramolecular arrangement of both compounds is discussed with relation to the structure of analogous aluminium and gallium complexes, and the role played by the coordination centre on the molecular assembly is analyzed. It is shown that the steric congestion at the hydrogen bond donor and acceptor sites, as a result of changes in the N-alkyl substituents or the coordination centre environment, affect the strength of the intermolecular C–HO hydrogen bonds and may lead to the self-assembly switching of the bidentate Schiff base complexes.

The reaction of Et₃B with one equivalent of N-substituted salicylideneimine (HsaldR') yields the monomeric O,N-chelate complexes Et₂B(saldR'), where R' = Me (1) or Ph (2). The crystal structure of the resulting complexes has been determined by X-ray crystallography. The molecular structure of these complexes consists of monomeric four-coordinate chelates and their primary arrangement in the crystal structure is determined by the C–H⋯O_aryloxide hydrogen bonds. An extended crystal structure analysis reveals that the adjacent monomeric moieties of 1 are interconnected by C–H_imino⋯O hydrogen bridges resulting in a 1-D motif infinite H-bonded chain, whereas the crystalline complex 2 comprises dimeric molecules linked through a pair of intermolecular C–H_arom⋯O interactions. The supramolecular arrangement of both compounds is discussed with relation to the structure of analogous aluminium and gallium complexes, and the role played by the coordination centre on the molecular assembly is analyzed. It is shown that the steric congestion at the hydrogen bond donor and acceptor sites, as a result of changes in the N-alkyl substituents or the coordination centre environment, affect the strength of the intermolecular C–H⋯O hydrogen bonds and may lead to the self-assembly switching of the bidentate Schiff base complexes.

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(Aqua)lanthanide complexes with cucurbituril {[Gd(NO3)(H2O)4](C36H36N24O12)}(NO3)2·7H2O (1), {[Gd(NO3)(C2H5OH)(H2O)3](C36H36N24O12)}(NO3)2·5.5H2O (2), {[Ho(NO3)(H2O)4](C36H36N24O12)}(NO3)2·7H2O (3), {[Yb(NO3)(H2O)4](C36H36N24O12)}(NO3)2·6H2O (4), {[La(H2O)6(SO4)](C36H36N24O12)}(NO3)·12H2O (5), {[Gd(H2O)4]2(C36H36N24O12)3}Br6·45H2O (6), and {[Ce(H2O)5]2(C36H36N24O12)2}Br6·26H2O (7) were obtained in high yield by reaction of cucurbituril with aqueous solutions of lanthanide(III) species. The crystal structures of the compounds show a packing of 1:1, 2:2, and 2:3 in the (cucurbituril)lanthanide complexes in which cucurbituril plays a bidentate ligand role, and water molecules of the (aqua)lanthanide complexes form hydrogen bonds with carbonyl groups of the cucurbituril molecule. The guest water molecule is situated in the cucurbituril molecule cavity of 2 and 5. The crystal structure of 6 is a packing of three-deck sandwiches, built from alternating cucurbituril molecules and Gd(H2O)4³⁺ ions. The largest distance between outermost oxygen atoms in the sandwiches is 30.04 Å. (© Wiley-VCH Verlag GmbH, 69451 Weinheim, Germany, 2002)

A series of polycyano–polycadmate host clathrates including a methylviologen dication (MV2+), which is a strong electron acceptor, and an organic molecule, such as alcohols, haloalkanes, ethers and small aromatics, and two complexes built of a polycyano–polycadmate and MV2+ have been synthesized. Single crystal X-ray diffraction experiments on ten clathrates and the two complexes revealed their 3-D network polycyano–polycadmate structures constructed with Cd2+ ions and CN− bridges. The network structures are classified into five structure types. Type I, II and III were found in the clathrates, and Type IV and V were found in the two complexes. Type I and II have cage-like cavities and each of the cavities includes one guest, MV2+ or an organic molecule. Type III has a channel-like cavity where MV2+ ions and organic molecules are included. Type IV and V have 3-D cavities, the shape of which is neither cage-like nor channel-like, for embracing MV2+. Although all compounds were colorless and the formation of a charge transfer complex between MV2+ and a neutral guest in the clathrates was not confirmed from the crystal structure data and diffuse reflectance spectra, some of them showed a color change from colorless to blue on UV irradiation, which arose from the reduction of MV2+ to a methylviologen radical cation MV+&z.rad;.

The crystal structure analysis of model organogallium amine‐alkoxides Me2Ga(OCH2CH2CH2NH2) (2) and [Me2Ga{μ‐OCH2CH(CH3)NH2}]2(3), demonstrate how hydrogen bonding can effectively compete with metal−ligand coordination preferences in determining the molecular and crystal structure and how conformational changes in a ligand and increased steric bulk on the carbon atom adjacent to the amine group can impart on a network morphology and molecular aggregations.

Reaction of M(^tBu)₃ with anthranilic, salicylic and ortho-toluic acids yields [(^tBu)₂M(μ-O₂CC₆H₄-2-NH₂)]₂, M = Al (1), Ga (2), [(^tBu)₂Ga(μ-O₂CC₆H₄-2-OH)]₂ (3), and [(^tBu)₂Ga(μ-O₂CC₆H₄-2-Me)]₂ (4), respectively. Reaction of anthranilic acid with two equivalents of Al(^tBu)₃ allows for the isolation of (^tBu)₂Al(μ-O₂CC₆H₄-2-NH₂)Al(^tBu)₃ (5). Compounds 1–5 have been characterized by NMR and IR spectroscopy, mass spectrometry, and X-ray crystallography. The presence of intra-molecular hydrogen bonding, in compounds 1–3, is probed by the orientation of the aromatic rings. Compound 5 is proposed to be a Lewis acid stabilized complex of the intermediate in the synthesis of compound 1.

Summary.:  [Cu(tn)2Ni(CN)4]2ċ4H2O and Cu(tn)2Ni(CN)4 (tn = 1,3-diaminopropane) were prepared and characterized. The hydrate is unstable on air and readily dehydrates to Cu(tn)2Ni(CN)4. Crystal structure analysis of the hydrate at 150 K revealed a novel tetranuclear molecular structure of the tetracyanonickellate. The building elements are two [Cu(tn)2]2+ cations (coordination numbers of Cu: 5 and 6, respectively), two [Ni(CN)4)2− anions, and crystal water. The two cations are linked by one tetracyanonickellate anion via bridging cyano groups placed in cis positions. The second anion is bound weakly (Cu-N = 2.82 Å) via one μ2-bridging cyano ligand. The tetranuclear molecules and pairs of solvate water molecules are linked by strong hydrogen bonds, thus forming infinite planes which are linked in the third dimension by considerably weaker hydrogen bonds.

Preparation and crystal structures of two polymorphs of Cu(tn)Ni(CN)4(tn=1,3-diaminopropane) are described. The blue polymorph is orthorhombic (space group: Pbca, Z=4, cell dimensions: a=9.466(4), b=12.268(12), c=19.097(10) Å), the violet one monoclinic (space group: I2/c, Z=8, cell parameters: a=16.815(16), b=9.606(3), c=21.252(20) Å, β=91.75(5)°). In both polymorphs, a rare case of T-type bridging tetracyanonickellate anion is present. The copper atoms are pentacoordinated by one chelate bonded tnmolecule and three N atoms from bridging cyano groups. The metallacycles prevail in chair conformation. The polymorphs differ in the dimensionality of the structure: the blue polymorph exhibits a 2D structure, the violet one a 3D arrangement. Herstellung und Kristallstrukturen von zwei Polymorphen des Cu(tn)Ni(CN)4(tn=1,3-Diaminopropan) werden beschrieden. Das blaue Polymorphe ist orthorombisch (Raumgruppe Pbca, Z=4, Zelldimensionen: a=9.466(4), b=12.268(12), c=19.097(10) Å), das violette monoklin (Raumgruppe I2/c, Z=8, Zellparameter: a=16.815(16), b=9.606(3), c=21.252(20) Å, β=91.72(5)°). In beiden Fällen liegt der seltene Fall eines überbrückenden Tetracyanonickelatanions vom T-Typ vor. Die Kupferatome werden durch ein chelatisiertes tn-Molekül und drei Stickstoffatome der Cyanobrücken fünffach koordiniert. Die Metallacyclen liegen in der Sesselkonformation vor. Die Polymorphen unterscheiden sich voneinander in der Dimensionalität der Struktur: das blaue Polymorphe ist zweidimensional, das violette dreidimensional.

Synthesis and single-crystal X-ray structures are recorded for three adducts of SbF3with different azacrown ethers. [SbF3·H2O·L1], 1,(L1= 12,13-benz-1,10-di(azamethyl)-4,7-dioxacyclotetradecane-1,14-dione), triclinic, $$P\bar 1$$ , a= 11.234(2), b= 11.691(2), c= 8.869(2) Å, α = 94.66(3), β = 113.12(3), γ = 67.82(3)°, Z= 2. [SbF3Cl·H2O·(HL2)], 2, (L2= monoaza-18-crown-6), orthorhombic, P212121, a= 8.763(2), b= 13.003(3), a= 16.836(3) Å, Z= 4. [(SbF3)2Cl2·(H2L3)], 3,(L3= 1,10-diaza-18-crown-6), triclinic, $$P\bar 1$$ , a= 8.284(2), b= 9.016(2), c= 9.134(2) Å, α = 82.92(3), β = 65.24(3), γ = 63.38(3)°, Z= 1. All three structures include SbF3neutral molecules in the pyramidal mode and the antimony second coordination sphere is completed up to six in different fashions. In 1the dimeric (SbF3)2adducts are made up due to the involvement of the symmetry-related fluorine atom in coordination. The distorted octahedron is then completed by water molecule and carbonyl oxygen of L1. The neutral molecules are joined by coordination and hydrogen bonds in the infinite ribbons. 2and 3are both comprised of neutral and charged species also bounded via coordination and hydrogen bonds. L2and L3in the complexes adopt the form of single and double-charged cations, respectively. The inorganic backbone unites the neutral SbF3molecules and chloride anions in the alternative mode. The sixth coordination site in the antimony polyhedron is completed by the water molecule in 2and the ethereal oxygen atom in 3. Alignment of the inorganic entities within the structures of 2and 3is strikingly similar. Hydrogen bonding patterns are discussed.

The crystal structure of 25,27‐dihydroxy‐26,28‐bis(diethoxyphosphoryloxy)‐tert‐butylcalix[4]arene (1) (hexane solvate, 1:1) was determined by x‐ray crystallography. The crystal data are P21/n, a=  12.652(1) Å, b=  12.564(2) Å, c=  18.781(4) Å, β  =  105.56(1)°, V=  2876.0(8) Å3, Z=  2. In this complex the molecule adopts a 1,2‐alternateconformation. Both the calixarene and hexane molecules are centrosymmetric. The phenol units in the asymmetric part of the calix are inclined with respect to the main macrocyclic plane by 115.46(6)° and 128.01(7)° for the phosphorylated and the non‐phosphorylated ring, respectively. Self‐inclusion of the ethyl chains in the half‐cavities is observed. One intramolecular O—H…O and several intermolecular C—H…O hydrogen bonds are present. In the 1H NMR spectrum one average AX spin system for methylene bridge protons can be interpreted as fast (on the NMR time‐scale) interconversion of non‐phosphorylated phenol fragments. © 1998 John Wiley & Sons, Ltd.

AbstractMg(C5H5N)4(NCS)2, C22H20N6S2Mg, is monoclinic, space group is C2/c, with a= 12.379(4), b= 13.093(5), c= 15.060(6) Å,β = 107.35(3)°, V= 2330(2)Å3, Z= 4,Dcalc= 1.303 g cm−3, μ(CuKα) = 24.664 cm−1, F(000) = 952.0. The structure consists of centrosymmetric monomeric units in which the Mg(II) cation is octahedrally coordinated to the N-atoms of four pyridines and two trans-coordinated isothiocyanate ligands. The structure is similar to those of [M(C5H5N)4,(NCS)2], where M = Fe, Co, Ni.

The structures of 1.1'-dimethyl-biisoquinoline-N.N'-dioxide (1) and of its 2:1 coordination complex with europium trichloride (2) have been determined by single-crystal diffractometry. The complex has a sevenfold coordination for Eu3 + via three Cl and four O donor atoms. The coordination polyhedron is a distorted pentagonal bipyramid with four oxygens and one chloride in the equatorial plane and two axial chloride ligands. Packing is of a van der Waals type and includes co-crystallized solvent molecules. Crystal -data: 1: P21,21,2, a = 14.032(4), b = 10.605(4), c = 5.242(1) Å, Z = 2; 2: P21/c, a = 12.829(10), b = 17.616(5), c = 43.863(17) Å, β = 91.34(4)°, Z = 8.

Zn(C6H7NUNCS)2, C14H14N4S2Zn, is orthorhombic, space group Fdd, a = 35.144(16), b = 18.119(4), c = 5.078(3)Å, Z= 8, Dcale= 1.430gcm-3, I= 17.036cm-1, F(000) = 1504. The structure consists of monomeric units in which the Zn(II) cation is tetrahedrally coordinated by two Ncs and two NMcpy atoms, the molecule showing twofold axial symmetry.

This review deals with the problem of the interaction of Si(IV), Ge(IV) and B(III) fluorides with crown ethers and their aza analogues. The crystallographic structures have been determined of the stable products obtained by the interaction of H2SiF6 solution with the following crown ethers: 18-crown-6 (18C6), monoaza-18C6 (MA18C6), 1,10-diaza-18C6 (DA18C6) and 1,7-diaza-15C5 (DA 15C5). The complexes obtained are stabilized by a system of H-bonds of the O-H... O, N-H. ... O, N-H...F and O-H ... F types. For H2GeF6 the adducts obtained are similar to those obtained using H2SiF6. The crystal structures of three new boron fluoride-containing complexes with 18-membered crown ethers are also described. During macrocycle complexation the guest entities undergo chemical transformations which are stabilized by creation of the H- bond system. The results of vibrational and NMR spectra are also discussed.

Stable products have been obtained from the interaction of GeO2-HF solution with 18-membered crown ethers, 1,10-diaza-l8-crown-6 and 18-crown 6. Complexes were characterized by X-ray analysis and IR spectroscopy. Both Ge(IV) aquafluorocompounds are isostructural with their Si analogues. It was established that in the host-guest type complexes the germanium moiety as a central atom has been stabilized in the form of octahedral complexes. The host-guest interaction occurs by means of O-H(W)...Ocr, OH...F and N-H...F hydrogen bonds.

An X-ray—diffraction study is reported for two molecular complexes containing 3,4-diamino-1,2,5-oxadiazole as guest (G) with 18-crown-6 (18-C-6) andcis-anti-cis-dicyclohexano-18-crown-6 (DCH-6B) as host. Both complexes are of the polymeric-chain structure with the guest molecule bridging two crown neighbours. ComplexI: [18-C-6*G*H2O], 1:1:1, monoclinic,P21/n,a=8.171(1),b=15.042(2),c=16.209(6) Å, ß=101.15(2)°, finalR-factor 0.068. ComplexII: [DCH-6B*G], 1:1, monoclinicC2/c,a=21.212(4),b=9.380(2),c=13.049(3) Å, ß=108.61(3)°, finalR 0.047.

The crystal structure of a-d-mannosido-benzo-18-crown-6·KSCN (1) was solved by X-ray single crystal diffractometry. C28H36O10·KSCN is orthorhombic, space groupP212121 withZ=4,a=8.035(4),b=9.960(2),c=38.83(2) Å,Mr=629.8,V=3103.6 Å3,Dx=1.347 g cm-3, µ(CuKa)=2.53 mm-1, ?=1.54178 Å,F(000)=1324. FinalR=0.043 for 1139 unique observed reflections measured at room temperature. The potassium ion is surrounded by a nearly planar hexagon of oxygen atoms of the macrocyclic ring and lies on the plane formed by those atoms. Hexagonal pyramidal coordination is completed by the nitrogen atom of the thiocyanate anion. The SCN ion was found on the face of the macrocyclic ring opposite that for the chiral mannopyranoside moiety. The molecular structure of a-d-mannosido-18-crown-6 (2) and the structure of molecular complexes of2 and a-d-glucosido-benzo-18-crown-6 (3) were studied by molecular mechanics methods. The results suggest enthalpy driven selectivity of complexation of the phenylalanine methyl ester (4) by2 and both enthalpy and entropy effects in selective complexation of4 by3.

The crystal structures of layered clathrate inclusion compounds of Ni(CNS)2 (4-methylpyridine)4 with 1-bromonaphthalene (I) and azulene (II) were analyzed by x-ray single-crystal diffractometry [crystal data: I-C46H42N6S2Br2Ni; a=11.88(1), b=11.82(1), c=32.79(3), ß=102.0(1), Z=4, P21/c; II-C46H44N6S2Ni; a=11.51(2), b=11.64(1), c=32.98(2), ß=103.4, Z=4, P21/n]. Disordering of guest molecules in I is concluded, based on x-ray study, and positions of the guest (each of the two symmetry independent molecules disordered over two orientations) have been refined. In II disoder of guest-azulene is also observed but only one from the two symmetrically independent guest molecules could be located from the x-ray data. The empirical force field calculations were performed for I and II. The results were used for location of the second azulene molecule and for discussion of the disorder mole (short or long-range).

The crystal structure of the non-clathrated a-Ni(NCS)2 (4-Vinylpyridine)4 complex was solved and refined to R=0.056 (crystal data: a=11.27(3), b=16.86(1), c=32.06(1) Z=8, V=6092 Å3;Pbca; dx=1.30 g. cm-3). The complex molecule adopts an asymmetric, windmill conformation of the four pyridine ligands. The a-phase was used as a solid substrate for clathration of liquid o-, m- and p-xylene, at 25°C. The composition of the products, the enthalpies of clathration and kinetic course of the processes were investigated. The clathration enthalpies, per mole of the host, are equal to 17.07, 14.1 and 21.77 kJ and correspond to the 1.05, 1.11 and 1.30 guest/host molar ratios for, respectively, ortho, meta and para-xylene. The clathration rates follow the order para>ortho>meta. The results are discussed from the structural point of view.

A detailed analysis of the thermokinetic course of the reaction a-Ni(NCS)2(4-methylpyridine)4+xylen-e»ß-Ni(NCS)2 (4-methylpyridine)4·(xylene) (at 25 °C), for 21 samples of purep-xylene andm-xylene, as well as two-and three-component mixtures of theo-,m-andp-isomers was performed by using the dynamic optimization method. The mechanism of the reaction is discussed. Firstly, a relatively rapid a»ß-phase transformation and uptake of 60–80% of the total guest takes place. Then follows the slower diffusion-controlled absorption of xylene up to the maximum filling corresponding to 1:1 guest/host stoichiometry.

The crystal structure of the inclusion complex of phenol in the matrix formed by the trans isomer of meta, meta'-bis-diisopropoxyphosphoryldibenzo-18-crown-6 was determined by X-ray diffraction methods. The molecular structure of the crown ether and the packing of the molecules in crystal is discussed. The statistical disorder of the phenol molecule in two positions with occupancy of 0.5 is due to the location of the molecule on the crystallographic two-fold axis. Additionally, the disorder of the phosphoryl substituent was revealed. Interaction between the hydroxyl group, as well as the hydrogen atom in the ortho position of the phenol with the system of oxygen atoms of the crown ether in the crystal influences the conformation of the macrocycle. In solution the host and guest molecules are associated by the hydrogen bonds formed between the hydroxyl group of phenol and the oxygen atom of the exocylic phosphoryl group of the crown ether.

Single crystal X-ray analysis of the 1:1 complex (I) between the cis-anti-cis- isomer of dicyclohexano-18-crown-6 (DCH-6B, host - H) and 6-chloro-7-sulphamido-3,4-dihydro-1,2,4-benzo-thiadiazine-1, 1-dioxide (hypothiazide, guest - G) is reported. Crystals of (I) are triclinic, space group P1, a = 17.838(4), b = 14.164(3), c = 14.332(3)Å; α = 90.51(4), β = 110.82(4), γ = 97.61(3)° and Dcalc = 1.387 gom-3 for Z = 4. The final R-factor is 0.087 for 8886 reflections. The crystal packing is characterized by two types of chains where hydrogen bonding joins crown ether and guest entities. The chains differ by acetone molecule inclusion which is H-bonded to one of the guest imino groups. Between the individual chains there are only van der Waals interactions. Host molecules adopt D3d and Ci conformations in the complex.

Four crystalline molecular complexes between antimony(III) fluoride and 18-membered crown ethers have been obtained and their structures investigated by single crystal X-ray diffraction techniques: [18-crown-6·SbF3], C12H24F3O6Sb,P212121,a=8.328(4),b=11.573(4),c=18.094(4)Å,V=1744(1)Å3,Z=4; [benzo-18-crown-6·SbF3], C16H24F3O6Sb,P21/n,a=10.490(2),b=13.714(1),c=13.442(2)Å, ß=101.94(1)°,V=1892(1)Å3,Z=4; [cis-syn-cis-dicyclohexano-18-crown-6·SbF3·CH3OH], C21H40F3O7Sb,P21/n,a=8.270(4),b=23.386(3),c=12.772(1)Å, ß=96.31(2)°,V=2455(1)Å3,Z=4; [cis-anti-cis-dicyclohexano-18-crown-6·SbF3], C20H36F3O6Sb,Pna21,a=21.091(8),b=12.829(5),c=8.437(3)Å,V=2283(2)Å3,Z=4. All species are the perching-type complexes with the antimony fluoride above the cavity and the metal lone pair pointed toward the center of the crown ring. The antimony atom interacts with all six crown oxygen atoms with Sb-O distances of 2.837(2)–3.344(2) Å. The antimony atom is displaced from the least square plane of the crown oxygen atoms at the distances of 1.288–1.383 Å.

X-ray diffraction studies are reported for six indolinones. The results show that two different types of associates are present in the crystal state of the compounds having an NH group. The indolinone molecules without any substituents form cyclic dimers while those with one or two methyl groups attached to the C3 atom of the lactam ring form infinite hydrogen bonded chains. It is confirmed that the lactam moiety forms a typical planar amide structure with no sign of the enol form present.

An X-ray diffraction study is reported for three molecules of salts containing a cation with a positive charged 2,3-diphenyltetrazolium ring. The results confirm aromatic structure of the tetrazole ring and the delocalization of charge on the whole molecules of the cations. The molecular geometry obtained is compared with that for free mesoionic 2,3-diphenyltetrazoles which have already been studied and the ring parameters do not reveal significant differences. But is shows that the geometry of the (NNO)- exocyclic group is changed as a result of alkylation. Compound I C13H12N5Cl, P21/a,a=16.934(4),b=6.575(1),c=26.121(4) Å, ß=108.15(2)°, II C14H13N6OI, P312,a=10.774(3),c=12.821(4) Å, IV C26H20N8Cl2, C2/c,a=22.316(4),b=6.6903(7),c=20.437(3) Å, ß=92.51(1)°.