Hydrogen-bonded urea-anion host lattices. Part 2. Crystal structures of inclusion compounds of urea with tetraalkylammonium bicarbonates

New inclusion complexes (C₂H₅)₄N⁺HCO ₃ ^– ·(NH₂)₂CO·2H₂O (1) and (n-C₄H₉)₄N⁺HCO ₃ ^– ·3(NH₂)₂CO (2) have been prepared and characterized by X-ray crystallography. Crystal data, MoK radiation:1, space groupP2₁/n,Z=8,a=9.356(1),b=29.156(4),c=12.161(1) Å, =90.03(1)°,R _F =0.062 for 2214 observed data;2, space groupP,Z=2,a=8.404(2),b=12.352(2),c=14.377(4) Å,a=88.20(2), =89.56(2), =71.68(1)°,R _F =0.052 for 3092 observed data. In both compounds the tetraalkylammonium ions are sandwiched between puckered layers, which are constructed from [((NH₂)₂CO)₂(HCO ₃ ^– )₂], ribbons, each composed of centrosymmetric hydrogen-bonded urea dimers and bicarbonate dimers, by lateral linkage through water molecules in1, and by direct cross-linkage of an alternate, parallel arrangement of the urea/bicarbonate and complementary urea ribbons in2. Supplementary Data relating to this article have been deposited with the British Library as Supplementary Publication No. SUP 82201 (40 pages).     

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

New inclusion complexes (C2H5)4N+CH3CO-°*4(NH2)2CS(1), (n-C3H7)4N+[(CH3CO2)2H]-°2(NH2)2CS (2), (n-C4H9)4N+[(CH3CO2)2H]-°2(NH2)2CS (3) and (CH3)4N+CH3CO2-°(NH2)2CS(4) have been prepared and characterized by X-raycrystallography. Crystal data, MoK radiation: 1, space groupC2/c, a = 28.702(4), b = 8.457(1), c =22.906(7) Å, = 98.91(1)°, Z = 8, and RF = 0.048for 2587 observed data; 2, space group P2/n, a = 8.536(2), b = 8.613(1), c = 18.360(2) Å, = 90.66(2)°, Z = 2, and RF = 0.045 for 1637 observed data; 3,space group P¯1, a = 8.771(3), b = 10.720(1), c = 16.742(2) Å, = 99.08(6), = 94.07(2), = 95.25(2)°, Z = 2, and RF = 0.063 for 2736 observed data; 4, space group P21/n, a = 8.421(3), b = 16.532(6), c = 8.628(3) Å, = 90.25(3), Z = 4, and RF = 0.050 for 1507observed data. In the crystal structure of 1, the thiourea moleculesand acetate ions constitute two channel systems aligned parallel to the[110] and [¯110] directions, with thetetraethylammonium cations accommodated in a single column withineach channel. In the crystal structure of 2, hydrogen-bondedcentrosymmetric thiourea dimers and acetate dimers are alternatelyarranged to form a zigzag, puckered ribbon running parallel to [10¯¯1], and the stacked columns of cations are sandwichedbetween undulatory wave layers constructed from the parallelarrangement of [((NH2)2CS)2((CH3CO2)2H)-] ribbons. In the crystal structure of 3,zigzag hydrogen-bonded thiourea ribbons are linked by dimeric acetateanions existing in two different conformations to generate puckeredlayers matching the (002) planes, and the (n-C4H9)4N+ cations occupy the intervening space. Incompound 4 the cations are accommodated in pseudo-channelsgenerated from infinitely extended thiourea-acetate composite ribbons.     

Inclusion Compounds of Thiourea and Paralkylated Ammonium Salts. Part VII. Hydrogen-Bonded Host Lattices Constructed from Thiourea and Anionic Species Derived from Benzoic Acid

New inclusion complexes (n-C₃H₇)₄N⁺C₆H₅CO ₂ ^– · 3(NH₂)₂CS (1), (n-C₄H₉)₄N⁺[(C₆H₅CO₂)₂H]^–·6(NH₂)₂CS (2) and (C₂H₅)₄N⁺C₆H₅CO ₂ ^– ·(NH₂)₂CS (3) have been prepared and characterized by X-ray crystallography. Crystal data, MoK radiation: 1, space group P2₁2₁2₁, Z = 4, a = 8.544(3), b = 14.588(4), c = 24.448(4) Å, and R1 = 0.062 for 1536 observed data; 2, space group Pbcn, Z = 4, a = 24.938(3), b = 8.911(1), c = 23.733(9) Å, and R1 = 0.055 for 2132 observed data; 3, space group P2₁2₁2₁, Z = 4, a = 9.996(2), b = 10.122(4), c = 18.350(2) Å, and R1 = 0.049 for 1180 observed data. In the crystal structure of 1, the (n-C₃H₇)₄N⁺ cations are stacked in a single column and accommodated within each channel built up by wide thiourea ribbons and benzoate ions via N—H···O hydrogen bonds. In the crystal structure of 2, the tetrabutylammonium cations are arranged in a zigzag column within each channel built of parallel corrugated thiourea layers that are inter-linked by dimeric [(C₆H₅CO₂)₂H]^– groups through N—H·O hydrogen bonds. In compound 3 the (C₂H₅)₄N⁺ cations are accommodated in pseudo-channels generated from infinitely extended thiourea-benzoate composite ribbons.     

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.     

Unsymmetrical Quaternary Ammonium Cations R3R′N+ as Guest Templates for the Generation of Novel Host Lattices Constructed from Thiourea and Oxocarbon Anions

Abstract

New inclusion complexes (n-C₄H₉)₃(CH₃)N⁺HC2O-4.(NH2)2CS⁺HC₂O^? ₄·(NH₂)₂CS·(½)H₂C₂O₄ (1), [(C₂H₅)₃(n-C₃H₇) N⁺]₂CO^2- ₃·6(NH₂)₂CS (2) and 2[(CH₃)₃(C₆H₅)N⁺]₂ CO^2- ₃·11(NH₂)₂CS. H₂O (3) have been prepared and characterized by X-ray crystallography. Crystal data, MoKα radiation: 1, space group Fdd2, a=18.603(3), b=63.661(8), c=7.830(1)Å, Z=16, and R_F =0.0648 for 1297 observed data; 2, space group P 1, a=12.593(2), b=13.075(2), c=16.238(2) Å, α=76.16(1), β=71.17(1), γ=66.32(1)°, Z=2, and R_F =0.041 for 4570 observed data; 3, space group P 1, a=11.605(2), b=17.059(3), c=22.779(5) Å, α=109.46(3), β=92.72(3), γ=107.07(3)°, Z=2, and R _F =0.081 for 5105 observed data. In the crystal structure of 1, the thiourea molecules, hydrogen oxalate ions and oxalic acid molecules build a three-dimensional network containing two fused channel systems that are arranged alternately along the [101] and [101] directions, with the tri-n-butylmethylammonium cations arranged in a zigzag column within each channel. Compound 2 features a three-dimensional open host structure in which two channel systems extend parallel to the [100] and [010] directions, which accommodate stacked columns of triethyl-n-propylammonium cations. In the crystal structure of 3, infinite thiourea chains and thiourea-carbonate layers are connected to generate a unidirectional channel host lattice that accommodates straight columns of trimethylphenylammonium cations.     

Hydrogen-Bonded Urea-Anion Host Lattices. Part 4. Comparative Study of Inclusion Compounds of Urea with Tetraethylammonium and Tetraethylphosphonium Chlorides

New inclusion complexes (C₂H₅)4E+Cl-2(NH2)2CO(1, E = N; 2, E = P) have beenprepared and characterized by X-ray crystallography. Crystal data, MoK radiation: 1, space group P21/c,Z = 4, a = 10.492(6), b = 14.954(8), c = 10.335(6) Å, = 91.02(5)°, R _F = 0.050 for 1527 observed data; 2, space group Pmn21, Z = 2, a = 7.446(1), b = 9.200(2), c = 12.753(3) Å, R _F = 0.079 for 519 observed data. In compound 1 the tetraethylammonium ions are sandwiched between puckered layers, which are constructed from the linkage of chloride ions and wide urea ribbons each composed of a broadside arrangement of centrosymmetric hydrogen-bonded urea dimers. In the crystal structure of 2, hydrogen-bonded urea ribbons running parallel to [100] are connected by chloride ions to generate a sawtooth wave layer, and stacked columns of tetraethylphosphonium cations are sandwiched between adjacent layers.Supplementary Data relating to this article have been deposited with the British Library as Supplementary Publication No. SUP 82216 (11 pages).     

Structural characterization of a copper(II) complex containing oxidative cyclization of N-2-(4-picolyl)-N′-(4-methoxyphenyl)thiourea,new ligands of 4-picolylthiourea derivatives and the precursor molecular structure of oxidative cyclization of N-(2-pyridyl)-N′-(4-methoxyphenyl)thiourea

Three new compounds of aryl thiourea derivatives, namely N-2-(4-picolyl)-N′-(4-methoxyphenyl)thiourea (L1), N-2-(6-picolyl)-N′-(4-methoxyphenyl)thiourea (L2) and N-2-(4-picolyl)-N′-(4-nitrophenyl)thiourea (L3), and the new copper(II) complex [Cu(4PicTz4OMePh)(OAC)(EtOH)] (C1), as a result of oxidative cyclization of the ligand (L1), were synthesized. In addition, pure precursor (P1), as the product of the oxidative cyclization of N-(2-pyridyl)-N′-(4-methoxyphenyl)thiourea (L4), was isolated and characterized. Ligands (L1) and (L2) were characterized by ¹H and ¹³C NMR and single crystal X-ray analysis. ¹H NMR spectroscopy showed strong hydrogen bonding interactions between N′H-functionalities and the pyridine nitrogen atoms as well as weak intermolecular hydrogen bonding between the thione sulfur and the NH hydrogen. Structural studies of complex (C1) showed that the copper ion is five-coordinated with a square-pyramidal environment. The oxidative cyclization of ligand (L1) results in an anionic bidentate ligand in complex (C1). Both ligand (L1) and precursor (P1) crystallize as centrosymmetric dimers.     

Heterocalixarene Inclusion Chemistry. Structure of a Crystalline Host-Guest Complex Including endo-Calix Ethyl Acetate and exo-Calix Clustering of Water

The X-ray crystal structure of the solvent inclusion compound formed between heterocalix[8]arene 1, ethyl acetate and water (1 : 1 : 4.5) has been studied. The compound crystallized in tetragonal space group I4₁/a, a = b = 21.278(3), c = 31.290(4) Å, V = 14167(4) ų, Z = 8. The host molecule, incorporating benzimidazol-2-one and 2,5-dimethoxy-1,3-phenylene subunits in an alternate cyclic arrangement, forms an almost perfectly closed cavity which encapsulates one solvent ethyl acetate guest molecule. Water molecules being entrapped in the lattice cages in the form of cyclic and linear clusters bind the bulky inclusion complexes via H-bonds in infinite layers. Two symmetry center related benzimidazole-2-one moieties of two hosts from neighbouring layers in the crystal lattice are arranged such that they partially overlap exhibiting stacking interaction.     

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.     

Syntheses and crystal structures of two magnesium–tetrazole compounds in salt and polymeric forms

Two alkaline earth–tetrazole compounds, namely catena‐poly[[[triaquamagnesium(II)]‐μ‐5,5′‐(azanediyl)ditetrazolato‐κ³N¹,N^1′:N⁵] hemi{bis[μ‐5,5′‐(azanediyl)ditetrazolato‐κ³N¹,N^1′:N²]bis[triaquamagnesium(II)]} monohydrate], {[Mg(C₂HN₉)(H₂O)₃][Mg₂(C₂HN₉)₂(H₂O)₆]_0.5·H₂O}_n, (I), and bis[5‐(pyrazin‐2‐yl)tetrazolate] hexaaquamagnesium(II), (C₅H₃N₆)[Mg(H₂O)₆], (II), have been prepared under hydrothermal conditions. Compound (I) is a mixed dimer–polymer based on magnesium ion centres and can be regarded as the first example of a magnesium–tetrazolate polymer in the crystalline form. The structure shows a complex three‐dimensional hydrogen‐bonded network that involves magnesium–tetrazolate dimers, solvent water molecules and one‐dimensional magnesium–tetrazolate polymeric chains. The intrinsic cohesion in the polymer chains is ensured by N—H...N hydrogen bonds, which form R₂²(7) rings, thus reinforcing the propagation of the polymer chain along the a axis. The crystal structure of magnesium tetrazole salt (II) reveals a mixed ribbon of hydrogen‐bonded rings, of types R₂²(7), R₂²(9) and R₂⁴(10), running along the c axis, which are linked by R₂⁴(16) rings, generating a 4,8‐c flu net.     

Crystalline Inclusion Compounds Derived from Derivatives of Mandelic Acid. Host Synthesis, Inclusion Formation, and X-Ray Structures of a Free Host Compound and of DMSO Inclusion Complexes in Both Racemic and Optically Resolved Forms

New chiral host compounds based on mandelic acid derivatives having methyl (6a, b and 8a, b) or bromo substituents (7a, b) attached to the phenyl ring of mandelic acid and involving additional aromatic groups were synthesized. The inclusion properties of both the racemic and the optically resolved host species are reported, including solvent co-crystallization as well as chiroselective and vapour sorptive inclusion. The structures of the free racemic host compound 6b and of the DMSO inclusion compounds of optically resolved and racemic 8 (8a and 8b, respectively) have been determined by X-ray analysis. Enantiomeric pairs of molecules in 6b form centro-symmetric dimers by mutual hydrogen bonding of one hydroxyl group while the other is involved in O-–H ... interactions. The guest molecules in the DMSO complexes of 8a and 8b are bound via hydrogen bonds to two host molecules related by translation along crystallographic axes. Parallels to previous hosts of this type are drawn.     

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.     

Molecular Recognition Based on Roof-shaped Diol Hosts. X-Ray Crystal Structures of Inclusion Compounds with Methanol, Pyridine and Toluene

Three crystalline inclusion compounds of roof-shapedtrans-11,12-bis(diaryl-hydroxymethyl)-9,10-dihydro-9,10-ethanoanthracene host molecules [where aryl is 4-methyl-phenyl (3) or4-t-butylphenyl (4)] have been studied by X-ray diffraction.The crystals of both the 3methanol (2 : 1) [a = 10.755(1),b = 11.571(1), c = 14.697(2) Å, = 75.12(1), = 89.67(1), = 87.13(1) °] and the 4-pyridine (2 : 3) compounds[a = 14.045(3), b = 14.366(3), c = 15.607(3) Å, = 91.62(1), = 103.65(1) and =116.05(1)°] are triclinic (P–1),while the 3toluene (1 : 1) complex has orthorhombic (Fddd) symmetry [a = 16.041(1), b = 25.008(1), c = 40.440(4) Å]. The host–guest interactions in both triclinic crystals are characterised by hydrogen bonds, with different patterns however. The determined crystal structures indicate a compromise between the requirement of hydrogen bonding on the one hand and close packing on the other. The highly symmetrical host framework in the toluene (1 : 1) complex of 3 seems to be the result of shape recognition, although atendency towards weak (C_methyl)H _arylinteractions [C_methyl = 3.533(7) and 3.674(6) Å] between the hosts was observed. The present roof-shaped diol hosts give excellent examples of molecular recognition by exhibiting two significantly different conformations, mostly depending on the proton donor/acceptor ability of the guest component. (O)H O intramolecular bonding between the two alcoholic groups characterises the so-called active form, whereas weaker (O)H and interactions stabilise the `inactive'conformation.     

X-ray and neutron diffraction studies of the crystal and molecular structure of the predominant monocarboxylic acid obtained by mild acid hydrolysis of cyanocobalamin. Part II. X-ray diffraction studies of wet crystals

The crystal and molecular structure of wet crystals of the O-monocarboxylic acid of cyanocobalamin has been determined. The molecule crystallizes in a monoclinic cell ofa = 14.845,b = 17.435,c = 16.243 A, β = 103.54°, space group P2₁,. Intensity data were collected by diffractometry and the structure solved by Patterson and Fourier methods. Refinement, initially by a least-squares process and latterly by Fourier methods, led to anR of 0.140. Disordered sites were found for the terminal atoms of side chaine; the identification of the acid grouping was not made with certainty. Sites for sixteen water molecules were determined.     

Indium-based liquid clathrates. II. Inclusion compounds derived from salts of the tetrachloroindate anion,InCl 4 − , and the crystal structure of [Li·15-c-5] [In(CH3)3Cl] (15-c-5=15-crown-5)

Indium(III) chloride reacts with 12-c-4 to give the 1:1 adduct [InCl₃·12-c-4]. This complex is a convenient In precursor to liquid clathrates. [InCl₃·12-c-4] reacts with LiCl to form [Li·12-c-4] [InCl₄]. When the reaction is carried out in the presence of an aromatic solvent such as toluene, a liquid inclusion complex forms readily. It has been determined that the C₆H₅CH₃:[Li·12-c-4] [InCl₄] ratio is 2. Alkylation of the 15-c-5 adduct of InCl₃ with methyllithium yields [Li·15-c-5] [In(CH₃)₃Cl]. The salt fails to form inclusion complexes with aromatic molecules. This compound has been characterized using single crystal X-ray diffraction. The molecule belongs to the monoclinic space groupP2₁/n, witha=7.515(2),b=18.952(6), andc=13.938(7) Å, =95.12(3)° andD _calc=1.43 g cm^–3 for Z=4. Least squares refinement based upon 2348 observed reflections led to a finalR=0.039. Supplementary Data relevant to this paper have been deposited with the British Library under number SUP82054 (20 pages).