Anthracene Based Bulky Diol Hosts. Crystal Structures of a Free Host and of Inclusion Compounds with Dipolar Guests

X-ray crystal structures are reported of a free host compound 1, comprising two diphenylmethanol terminal groups attached to a central 9,10-ethynyl substituted anthracene unit, and of three inclusion compounds of a fluoren-9-ol substituted analogous host 2 with acetone, dimethyl sulphoxide (DMSO) and dimethylformamide (DMF) as guest, respectively. Despite the presence of two hydroxyl groups in 1, there is no O–H...O hydrogen bond between the molecules in the guest free crystal – only weaker C–H...O interactions and van der Waals' type connections. In the inclusion compounds of 2, H-bonded 1:2 host–guest associates are formed, where each of the host hydroxyl groups binds to a guest oxygen atom. The orientations of the host–guest connections in these complexes vary, being E for acetone and Z for both DMSO and DMF guests, relative to the host anthracene unit. The DMSO and DMF inclusion compounds of 2 proved to be isostructural.     

Inclusion Compounds of Nitrosobenzenes with Cholic Acid and Deoxycholic Acid

The crystalline inclusion compounds of cholic acid (CA) and deoxycholic acid (DCA) with several nitrosobenzenes were prepared. The IR spectra and crystal structures of these compounds confirmed inclusion of the monomeric form of the C-nitroso compounds. The DCA compounds have 2 : 1 host:guest stoichiometry and P2₁ symmetry. Guest molecules are enclosed in channels and disordered. In the CA-nitrobenzene inclusion compound (1·CA) the host:guest stoichiometry is 1 : 1. The host molecules form typical CA bilayer aggregates and guest molecules are accommodated in helicoidal channels. The guest nitroso group is not coplanar with the phenyl ring; the torsion angle on the C–N bond is 8.6(8)°. The solid-state circular dichroism spectrum of 1·CA shows the negative Cotton effect at 780 nm corresponding to the n–^* electronic transition that can be associated with the P helicity of the guest molecule. The extremely weak magnitude of the Cotton effects exhibited by the DCA complexes points to a nearly planar arrangement of the NO group and the phenyl ring in the guest molecules.     

A New Functional Cyclophane Host. Synthesis, Complex Formation and Crystal Structures of Three Inclusion Compounds

A new macrocyclic host compound 2 having an octamethylsubstituted cyclophane structure with two intra-annular carboxylic acid functions has beensynthesized. The properties of crystalline inclusion formation are studied and X-ray crystalstructures of three inclusion complexes including acetic acid, propionic acid and acetone asthe guest molecules are reported. Inter-host channel formation with complexed guest moleculesaccommodated into the channels are typical features of the acetic acid and acetone 1 : 4 (host : guest) stoichiometric complexes being also hydrated species, while the propionicacid 1 : 2 complex is of the close packing type containing no additional water molecules.Systems of hydrogen bonds involving the host and guest functional groups are common toall structures. In the case of the acetic acid inclusion compound, a complex supramolecularhydrogen-bonded array comprising a bordering tricyclic assembly of eight molecular species exists.     

X-Ray Crystal Structure of Four Inclusion Complexes of the Novel Host Gossindane: An Oxidation Product of Gossypol

Gossindane, the oxidation product of gossypol, demonstrates inclusion properties towards four solvents chosen accidentally. The crystal data of these complexes with ethanol (I), ethylacetate (II), dichloromethane (III) and water (IV) are: (I): C26H30O6· 2C2H5OH, monoclinic, P2/c, a = 8.687(2) Å, b = 10.986(3) Å, c = 14.778(3) Å = 110.94° V = 1317 Å3, Z = 2, R = 0.069, N = 1368; (II): C26H30O6· 0.5C4H8O2, monoclinic, P21/c, a = 8.960(2) Å, b = 21.937(5) Å, c = 14.712(3) Å, = 111.98(2)°, V = 2681 Å3, Z = 4, R = 0.083, N = 2653; (III): C26H30O6· CH2Cl2, monoclinic, P21/c, a = 8.886(2) Å, b = 21.778(6) Å, c = 14.996(4) Å, = 111.31(3)°, V = 2704 Å3, Z = 4, R = 0.131, N = 1580; (IV): C26H30O6·2H2O, monoclinic, C2/c, a = 29.422(9) Å, b = 6.720(2) Å, c = 27.525(9) Å, = 117.43(2)°, V = 4830 Å3, Z = 8. R = 0.096, N = 2240.In the solvates H-bonded host molecules form bilayers with very similar structures and a nearly hydrophobic surface. Guest molecules are placed in channels formed between these bilayers and may be H- bonded to host molecules (ethanol). In the hydrate two water molecules using their H-bonding capacity incorporate gossindane molecules into bilayers.     

Synthesis and Inclusion Properties of the Host Compound 1,3-Dihydro-1,1,3,3-tetraphenylisobenzofuran. X-Ray Crystal Structures of the Free Host and of an Inclusion Compound with 1,4-Dioxane

A novel host molecule, 1, suitable for crystalline lattice-type inclusion, has been synthesized, and its cocrystal formation ability has been investigated. Host 1 proved to be of potential use for organic solvent separation and retrieval, and a promising auxiliary for solidification of certain odorous substances. The crystal structures of the solvent-free host 1, and its complex with 1,4-dioxane (1 : 1), have been determined by single crystal X-ray diffraction. The structure of 1 (guest-free) is triclinic, P , with a = 9.452(2), b = 10.359(3), c = 13.116(3) Å, = 101.80(2), = 106.53(1) and = 104.32(1)°. The spacious, propeller-like molecules are held together by weak van der Waals' forces. The dioxane inclusion compound is monoclinic, P21/a, with a = 15.050(1), b = 8.641(1) and c = 20.658(1) Å, and = 94.56(1)°, and contains two crystallographically independent guest molecules, both located around symmetry centres. The molecular packing seems to be governed by C—H···O type bonds (C···O = 3.31 and 3.48 Å) from the host to the dioxane oxygens.     

螯形二羟基主体分子的包结性能与其结构关系的研究

报道了螯形主体分子，反式－9，10－二－1'－萘基－9，10－菲二醇（1）， 能与多种含氮有机化合物，诸如喹啉、异喹啉、哌啶、二环已胺等形成包化合物； 而反式－9，10－二苄基－9，10－菲二醇（2）则不具有包结性能。还报道了这些 包结化合物的IR，粉末XRD的表征，用~1H NMR谱测定了它们的分子摩尔比，分别为 （1）／喹啉(1:2), (1)/异喹啉(1:2)，（1）／哌啶（1:2）和（1）／二环忆胺 (1:2)。用单晶X射线衍射法测定了（1）与二环忆胺包结物以及（2）的结构，结果 表明前者属正交晶系，空间群为Pnca(标准型Pbca)，晶胞参数: a = 1.6714(3) nm, b = 1.6875(3) nm, c = 1.7224(3) nm, V = 4.858 nm~3, Z = 8，形成了隧 道型配位笼状包合物。后者属三斜晶系，空间群为P1-bar，晶胞参数: a = 0. 8058(2) nm , b = 0.9715 (2) nm, c = 1.4437(3) nm, α = 109.59(3)°, β = 95.96(3)°, γ = 96.03(2)°, V = 1.0471 nm~3, Z = 2, 还比较了(1)和(2) 的结构差异，分析了(1)的结构和包结性能的关系。     

Triarylmethanol Host Compounds. Synthesis, Crystalline Complex Formation and X-Ray Crystal Structures of Three Inclusion Species

A variety of triarylmethanol compounds including benzo condensed and laterally substituted derivatives 1–10 have been prepared and shown to act as crystallinehosts for the inclusion of organic solvents involving protic polar, aprotic dipolar and apolar molecules. The inclusion ability is ratherhigh for aprotic dipolar solvents while protic polarcompounds are only rarely enclathrated. Host 9 is an exception, being also efficient with alcohols and amines. Compound3 displays no inclusion formation under theexperimental conditions. X-ray crystal structures of the inclusion compound 1acetone (2:1) and of two amineinclusion compounds of host 9 [9 n-propylamine(1:1), 9di-n-propylamine (1:1)] are reported showing the formation of H-bondedhost-guest associates as the common feature of supramolecular association.Supplementary data relating to this article have beendeposited with the British Library, No. SUP 82226 (10 pages).at Boston Spa, Wetherby, West Yorkshire, U.K., as Supplementary Publication.     

Diverse Modes of Solvent Inclusion in Crystalline Pseudopolymorphs of the Anthelmintic Drug Niclosamide

Single crystal X-ray structures of solvated forms of theanthelmintic drug Niclosamide reveal distinctly differentmodes of inclusion for different solvents. These modes are,respectively, cavity occupation by water molecules in 1 : 1niclosamide.H₂O, channel occupation by tetrahydrofuranmolecules in 1 : 1 niclosamide.THF, and intercalation bytetraethylene glycol molecules in 2 : 1 niclosamide.TEG. Inall three compounds the host drug molecule adopts the same,nearly planar conformation, which is maintained by anintramolecular N-H.O hydrogen bond. Host-guest recognitioninvariably involves hydrogen bonding between the drughydroxyl group and an oxygen acceptor atom of the solventmolecule. The observed modes of solvent inclusion can bereconciled with the behaviour of the crystals on heating.     

Exploring Clathrate Formation with an Optically Resolved Host. X-Ray Crystal Structure of the Inclusion Compound between (11S,12S)-(-)-9,10-Dihydro-9,10-ethanoanthracene-11,12-dicarboxylic Acid and n-Hexane (2 : 1)

The crystal structure of the inclusion compound formed between (11S,12S)-(-)-9,10-dihydro-9,10-ethanoanthracene-11,12-dicarboxylic acid, (1), and n-hexane (2:1) has been studied by X-ray diffraction. It crystallizes in the tetragonal space group P41 and represents a less common type of inclusion compound, which has helical and chiral structural elements. Helical chains, formed by hydrogen-bonded host molecules, wind around the 21 screw axes and encircle the guest molecules. Crystal data: a=b=17.478(1); c=12.021(1)Å, Z=4 host–guest 2:1 units, R=0.043, Rw=0.061 for 2225 observations with I > 3 (I). The general shape and conformational flexibility of 1 with respect to the requirements of inclusion formation and crystal packing are discussed.     

The Structure of New Host Molecules that form Channel Inclusion Compounds

1,3-Benzenediamine,N,N′-bis(4,6-dichloro-1,3,5-triazine-2-yl) and 1,3,5-Triazine,2,2′-[2-methyl-1,3-phenylenebis(oxy)] bis(4,6-dichloro) were synthesized as host molecules. The inclusion compound of 1,3-Benzenediamine,N,N′-bis(4,6-dichloro-1,3,5-triazine-2-yl) crystallizes in the monoclinic crystal system in space group C2/c. The host molecule occupies the space group 2-fold special position and packed in the crystal lattice in such a manner as to leave channels running along the c axis of a rectangular cross-section. It crystallizes with two molecules of acetone that are hydrogen bonded to the amino nitrogen atoms. Molecules of 1,3,5-Triazine,2,2′-[2-methyl-1,3-phenylene bis(oxy)]bis(4,6-dichloro) are packed in the crystal in such a manner as to leave channels of a trapezoid cross-section that are running along the a axis. Guest molecules such as metanol, ethanol, and ethyl acetate can be used to fill the channels. The crystal structures of two inclusion compounds are described.     

New Exo-Functional Cyclophane Hosts. Synthesis and Crystal Structures of Inclusion Compounds

The new cyclophane type host compounds 1–3, containing rigid aromatic units and two exo-topic carboxylic acid functions, have been synthesized. Crystalline solvent inclusions, involving the dicarboxylic acid hosts and their corresponding ester intermediates 6 (a–c), namely 1·DMSO (1:4), 2·pyridine (1:3), 3·pyridine (1:4), 6a·pyridine (1:2) and 6a·benzene (1:2), have been prepared and studied using X-ray diffraction on single-crystals. Moreover, X-ray structure analyses of the solvent-free crystals of the 6 (a, b) intermediates were also carried out for comparison. Co-crystals of the carboxylic hosts 1–3 contained H-bonded 1:2 host-guest associates as building blocks, together with additional space-filling guests, whereas only loosely bounded space-filling solvent molecules were found in the two solid inclusion compounds of the 6a cyclophane ester host. In addition to the mentioned conventional H-bond interactions between carboxylic hosts and their guests, the crystal structures proved to be held together by relatively weak C–H…O bonds besides the ordinary van der Waals' interactions. Packing relations, and the effects of structural variations, guest molecules and anisotropic packing forces on the conformation of the semi-rigid cylcophane ring have been discussed and compared in seven crystal structures.     

包结法拆分1,1'-联-2-萘酚:包结物的晶体结构及CD光谱

以D/L-缬氨醇为原料,通过二步反应得到价廉易得的拆分剂碘化(R)/(S)-N,N,N-三甲基-1-羟基-3-甲基-2-丁铵,采用包结拆分法,成功实现了对1,1′-联-2-萘酚(BINOL)的拆分.对具有(R)-构型的季铵盐与(R)-BINOL在甲醇中所形成包结物的晶体结构分析结果表明:I-离子桥联主体(拆分剂)的醇羟基和客体(BINOL)的酚羟基形成O-H…I-氢键,以及相邻层的主客体分子之间的C-H…O氢键相互作用是在包结物中实现手性识别的关键.同时对两个包结物的溶液和固体圆二色(CD)光谱进行了研究.     

Inclusion complexes of the natural product gossypol. Clathrate type inclusion complexes of gossypol with carbonyl group containing guests

The crystal structures of 2:1 inclusion complexes of gossypol with methyl propionate (GPMEP) and ethyl acetoacetate (GPEAA) have been determined by X-ray structure analysis. The crystals of GPMEP, C₃₀H₃₀O₈l/2 C₄H₈O₂, are monoclinic, space groupC2/c,a=11.079(3),b = 30.724(7), c = 16.515(5) Å, = 90.46(2)°,V = 5621(3) Å,Z = 8,D _x = 1.33 g cm^–3. The structure has been refined to the finalR value of 0.059 for 1899 observed reflections. The crystals of GPEAA, C₃₀H₃₀O₈l/2 C₆H₁₀O₃, are monoclinic, space groupC2/c,a=11.095(2),b=30.604(9),c = 16.955(5) Å, = 88.27(2)°,V = 5754(3) Å,Z = 8,D _x = 1.35 g cm^–3. The structure has been refined to the finalR value of 0.056 for 2502 observed reflections.In contrast to previously investigated inclusion complexes of gossypol the host molecules do not form centrosymmetric dimersvia hydrogen bonds. In the crystal structures the racemic gossypol is separated into enantiomers forming alternating bimolecular layers. Nearly perpendicular to these chiral bilayers run elongated cavities enclosed on each side by layers of opposite chirality. The surface of these layers is hydrophobic, the polar groups are hidden inside the layer. Guest molecules which are hydrogen bonded to the host are included in cylindrically shaped cavities. Possible hydrogen bonds between host and guest are analysed for this isostructural class of complexes.     

蝶形主体分子的设计、合成及其包结性能的研究

设计、合成了两种蝶形主体分子：2，5－二（三苯甲基）对苯二酚1，2，5－二（二苯甲基）对苯二酚2.1和2可与许多有机小分子形成配位包合物。用IR表征了主体分子1和2 的包结物， 用¹H NMR测定了主客体分子的摩尔比：1•DMF (1：2)，1•DMSO (1:2)，1 •吡啶 （1：2），1•环戊酮 （2：3）和2•DMF 1：2），2•DMSO （1：2），2 •THF （1：1），2•苯甲醛（1：2），2•苯乙酮 （1：2），2•2，5－己二酮 （1：1），2 •N－甲基－2－吡咯烷酮 （1：3）。单晶X-射线衍射分析了包结物2·苯甲醛的晶体结构，在分子间氢键的相互作用下晶体得以稳定。     

Inclusion Compounds of Thiourea and Peralkylated Ammonium Salts. Part IV. Hydrogen-Bonded Host Lattices Built of Thiourea and Formate Ions

New inclusion complexes(C2H5)4N+HCO2-·(NH2)2CS·H2O (1),[(C2H5)4N]2+[(HCO2)2H]-(HCO2-)·2(NH2)2CS(2), (n-C3H7)4N+HCO2-·3(NH2)2CS·H2O (3)and (n-C4H9)4N+[(HCO2)2H]-·2(NH2)2CS(4) have been prepared and characterized by X-ray crystallography. Crystal data, MoK radiation: 1, space group P21/c, a = 7.199(2), b = 16.851(2),c = 13.044(2) Å, = 100.13(2)°, Z = 4, and RF = 0.065 for 1011 observed data; 2, space group Pca21, a = 25.803(5), b = 7.190(2), c = 17.394(2) Å, Z = 4, and RF= 0.073 for 1515 observed data; 3, space group P21/n, a = 8.533(2), b = 9.423(5), c = 33.517(7) Å, = 90.44(2)°, Z = 4, and RF = 0.052 for 2521 observed data; 4, space group Pbca, a = 17.389(3), b = 16.622(2),c = 20.199(3) Å, Z = 8, and RF = 0.056for 1910 observed data. In both 1 and 2 the tetraethylammonium ions are sandwiched between puckered layers, which are constructed by the cross-linkage of a parallel arrangement of infinite chains. In 1 each chain is composed of twisted(thiourea–formate)2 tetramers bridged by water molecules, whereas in 2 it comprises an alternate arrangement of thiourea dimers and protonated formate trimers each formed by the linkage of a hydrogen diformate ion, [(HCO2)2H]-, to a formate ion via} a C–-H·sO hydrogen bond. In compound 3 two independent thiourea molecules are used to construct a hydrogen-bonded puckered layer normal to thec axis, whereas the remaining thiourea molecule, together with the formate ion and water molecule, generate another puckered layer that is parallel to the first one. Hydrogen bonding between these two types of layers gives rise to a network containing channels running parallel to the [100] direction, and the cations are stacked regularly within each column. In the crystal structure of 4, the thiourea molecules form hydrogen-bonded zigzag ribbons running parallel to the b axis, which are cross-linked by the dimeric formate moieties [(HCO2)2H]- to form a puckered layer, and the(n-C4H9)N+ cations occupy the space between adjacent layers.     

Supramolecular Inclusion Hosts Based on Amino Acid Compound Sources: Design, Synthesis and Crystalline Inclusion Behaviour. X-Ray Crystal Structures of Two Inefficient Host Compounds

A new design of crystalline hosts derived from amino acids, characterised by an amino- ethanol functional unit or its carbonamide structural derivative and appended aromatic residues including secondary substituents, is reported. The syntheses of corresponding compounds (1–15) are described. Crystalline inclusion formation is shown and discussed with reference to structural parameters of the host molecules. X-Ray crystal structures of compounds 3 and 11 have been determined in order to suggest reasons for their failure to show inclusion ability.     

Inclusion of quinolines by binaphthol: structures and selectivity

The enclathration selectivity of the host compound 2,2'-dihydroxyl-1,1'-binaphthyl, BINAP, towards the guests quinoline (Q), 2-methylquinoline (2MeQ), 6-methylquinoline (6MeQ) and 8-methylquinoline (8MeQ) were established by competition experiments as: BINAP.2(2MeQ) > BINAP.2Q > BINAP.2(8MeQ) > BINAP.2.5(6MeQ). The crystal structures of the inclusion compounds were elucidated and are all stabilised by (host)O-H...N(guest) hydrogen bonds. Thermal analysis yields the same sequence with respect to the relative stabilities. pH Control was employed to dramatically modify the selectivity profile of the pair of 2-methylquinoline (2MeQ) and 8-methylquinoline (8MeQ).     

Inclusion complexes of the natural product gossypol. Crystal structure of the 1 : 1 complex of gossypol with isovaleric acid

The crystal structure of the 1 : 1 lattice inclusion complex of gossypol with isovaleric acid has been determined by X-ray structure analysis. The crystals of C₃₀H₃₀O₈C₅H₁₀O₂ are monoclinic, space groupC2/c,a=28.835(7),b=9.063(2),c=26.880(4)Å, =109.66(1)°,V=6615(2) ų,Z=8,D _x = 1.25 g cm^–3, (CuK) = 7.14 cm^–1,T = 295 K. The structure was solved by direct methods and refined with isotropic thermal parameters to the finalR value of 0.132 for 1114 observed reflections. Hydrogen bonded gossypol molecules form columns along the [1 0 1] direction. These columns pack into layers parallel to the (101) plane. The layers of gossypol molecules are separated by the layers of isovaleric acid. The acid molecules are connectedvia a pair of O-H...O hydrogen bonds forming centrosymmetric dimers. There is no hydrogen bond interaction between the carboxylic acid dimers and gossypol molecules.     

Planar chiral dianthranilide and dithiodianthranilide molecules: optical resolution, chiroptical spectra, and molecular self-assembly

Planar chiral dianthranilide (1) was resolved to enantiomers with use of (-)-(1S,4R)-camphanoyl chloride as a chiral derivatizing agent. The (+)-1 enantiomer was assigned the S absolute configuration from the X-ray crystal structure of its N,N'-dicamphanoyl derivative. Optical resolution of dithionodianthranilide (2) was accomplished by inclusion crystallization with (R,R)-1,2-diaminocyclohexane, and the X-ray structure of the corresponding adduct revealed the (-)-2stereoisomer has the R configuration. A slow boat-to-boat ring inversion (DeltaG(++) = 24.1 +/- 0.1 kcal mol(-1)) causes racemization of (+)-1 in solution as manifested by a gradual decrease of the CD spectrum whereas, (-)-2 is configurationally stable at these conditions. The analysis of the CD spectra of the title compounds showed that the n-pi* Cotton effect signs are determined by the helicity of the skewed benzamide and thiobenzamide chromophores. The solid-state structures of the racemic and homochiral forms of 1 and 2 show different self-assembly patterns: the racemate (+/-)-1 prefers the cyclic R(2)(2)(8) hydrogen bond motif, whereas the crystalline DMSO solvates of (+/-)-1 and (+)-1 consist of 1D homochiral hydrogen-bonded assemblies generated by the C(6) motif. In the case of dithionolactams (+/-)-2 and (-)-2 two types of 1D networks were observed: in the racemate they are generated by the centrosymmetric R(2)(2)(8) and R(2)(2)(12) hydrogen bond motifs, whereas the molecules in the homochiral crystals are connected solely with use of the strongly nonplanar R(2)(2)(8) motif.