Crystal Structures of Two Calix[10]arenes Complexed with Neutral Molecules

Two calix[10]arenes were synthesized: the tert-butylcalix[10]arene (t-Bu-C10) and the detertbutylated analogue (H-C10). Both were crystallized from saturated solutions: t-Bu-C10 from a mixture of toluene and tetrahydrofuran (THF), H-C10 from acetone. In each case, complexes were obtained: H-C10, acetone 1:2 and t-Bu-C10, toluene, THF 1:2.5:0.5. The crystal structures of these twocomplexes and the different conformations of the macrocycles are presented here.For the first, the crystals are triclinic, space group Pmacr{1}, a = 9.037(2)Å, b = 11.447(2)Å, c = 15.197(3)Å, = 80.79(3)Å, = 84.96(3)°, = 88.60(3)°, V = 1545.7(5)ų, Z = 1; the complex with t-Bu-C10 is orthorhombic, space group Fmm2, a = 32.211(6)Å, b = 32.289(7)Å, c = 12.179(2)Å, V = 12667(4)ų, Z = 4. The complex from H-C10 shows a pleated loop conformation with H-bonds between acetone and hydroxylgroups. The complex from t-Bu-C10 shows several cavities, in the conesshaped by the phenol moieties and near the hydroxyl groups. The packingsare given for both crystals.     

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.     

Crystal Structure of a p-Benzylcalix[5]arene- pyridine Complex

p-Benzylcalix[5]arene.3py (py = pyridine) (1) crystallizes in the triclinic space group P1, a = 10.641(3), b = 13.975(3), c = 24.052(12) Å, = 94.60(4), = 91.51(4), = 111.46(2)°, V = 3312(4) ų, Z = 2. Refinement led to a final conventional R value of 0.065 for 5457 reflections. The calixarene is in a distorted cone conformation. Two pyridine molecules are hydrogen bonded to phenolic oxygen atoms and one of them is included in the hydrophobic cavity of the neighboring calixarene molecule along the a axis.     

Octa(p-hydroxy)octakis(propyloxy)calix[8]arene: The First Crystal Structure of a p-Hydroxy Calixarene

Octa(p-ydroxy)octakis(propyloxy)calix[8]arene.9(pyridine).2(H₂O) crystallises in the triclinic space group P-1, a = 14.083(2), b = 14.478(2), c = 15.652(2) Å, = 70.109(4), = 74.146(3), = 75.572(4)°, V = 2843(1) ų, Z = 1. Refinement led to a final R₁ value of 0.0757 for 4693 reflections. The calixarene sits around a crystallographic centre of inversion and is in the `chair-like' conformation. All p-hydroxyl groups form hydrogen bonds with either pyridine or water molecules leading the extended structure to be composed of infinite ribbons parallel to the [1,0,-1] direction.     

Large Calixarenes: Structure and Conformation of a Calix[16]arene Complexed with Neutral Molecules

A crystal of an inclusion compound between a calix[16]arene and molecules ofacetonitrile and dichloromethane, used as solvents, has been obtained and its X-raystructure studied. The cell is monoclinic, space group C2/c with a = 38.508(8) Å,b = 21.593(4) Å, c = 26.625(5) Å and = 121.34(3)°.The macrocycle is in the form of two superimposed celtic torcs connected by theirextremities.¹ Two acetonitrile molecules are situated in the middleof this double torc, two dichloromethane molecules are encapsulated in the pseudocalix[4]arenes obtained on both extremities of the torcs by the folding of the lastfour phenolic rings. A disorder is observed for the other acetonitrile and dichloromethanemolecules situated outside the macrocycle.     

Crystalline complexes of N,N'-ditritylurea (DTU) and N-tritylurea (NTU) hosts with molecular guests

This paper reports crystalline complexes of the new hosts N,N'-ditritylurea (DTU) and N-tritylurea (NTU) with various uncharged molecular guests. The crystal structures of the following complexes were elucidated by single crystal X-ray diffraction analysis at 115^oK: (I) 1:1 DTU-propanamide — space group C2/c, a=15.839Å, b=9.088Å, c=24.584Å, =111.05^o, Z=4; (II) 1:1 DTU-ethyl N-acetylglycinate — space group P1, a=9.010Å, b=10.800Å, c=19.810 Å, =105.29^o =94.33^o, =93.03^o, Z=2; (III) 2:1 NTU-N, N-dimethylformamide — space group Cc, a=29.614Å, b=8.906Å, c=16.127Å, =121.04^o, Z=4. The three crystal structures are stabilized mainly by a cooperative effect of hydrogen bonding between amide fragments displaced along the shortest axis of each crystal. This interaction occurs between host and guest in complexes I and II, and between host and host in complex III. The latter also represents a cage-type clathrate in which the guest molecules are accommodated in voids between the hydrophobic fragments of four neighboring NTU hosts. On the other hand, complexes of DTU are characterized by a more specific interaction between the two components, each guest molecule being inserted between two adjacent hosts (related by translation) and strongly bound to them via hydrogen bridges. These results illustrate a useful concept in the design of molecular species which can be potential hosts upon crystallization with neutral molecular guests. Supplementary Data relating to this article are deposited with the British Library as Supplementary Publication No. SUP 82022 (7 pages).     

Pinched-cone Calix[6]arene: New Synthesis of p- (1,1,3,3-tetramethylbutyl)calix[6]arene. Structure of its 1 : 3 Complex with Chloroform

A new method is described for the synthesis of p-(1,1,3,3-tetramethylbutyl)calix[6]arene isolated ina 30 % yield. For the first time the crystal structure isgiven. The crystals are monoclinic, space group C2/c,a = 24.144(5) Å, b = 14.093(3) Å,c = 26.972(5) Å, = 93.36(3)^circ, V = 9162(3) ų, Z = 4. The macrocycle with C2symmetry presents the pinched-cone conformation. It crystallizes with three chloroform molecules, two of them are positioned in the cones shaped by the phenol moieties; the third chloroform is located in the cavity near the hydroxyl groups; this solvent molecule is disordered around the 2 axis. The packing of the complex is described.     

A Bridged High-Spin Complex Bis-[Ni(II)( rac-5,5,7,12,12,14-hexamethyl- 1,4,8,11-tetraazacyclotetradecane)]-2,5-pyridinedicarboxylate Diperchlorate Monohydrate

A bridged high-spin complex,bis-[Ni(II)(rac-5,5,7,l2,12,14-hexamethyl-1,4,8,11-tetraazacyclotetradecane)]-2,5-pyridinedicarboxylate diperchlorate monohydrate has been obtained by reaction of [Ni(II)(rac-5,5,7, 12,12,14-hexamethyl-1,4,8,11-tetraazacyclotetradecane)](ClO₄)₂ and 2,5-pyridinedicarboxylic acid in aqueousalkaline (NH₄OH) medium. C₃₉H₇₇Cl₂N₉Ni₂O₁₃, chemical formula weight 1068.42, orthorhombic, P2₁2₁2₁, a = 11 .423(3) Å,b = 14.770(6) Å, c = 31.608(7) Å, = = =90.00°, V = 5333(3) ų, Z = 4, D_calc = 1.331 g cm^-3, _calc = 0.869 mm^-1, F(000) = 2272, T = 293(2), R = 0.0870 for 2686 observed reflections [I > 2(I)]. The complexincludes two folded [Ni(rac- Me₆[14]aneN₄)]²⁺ units havingopposite diastereomeric configuration. They are bridged through a dianion of2,5-pyridinedicarboxylic acid, with one Ni-atom coordinated to the O-atom ofthe 2-carboxylic group and the pyridine N-atom (forming a 5-membered chelatering), and with the second Ni-atom coordinated to both O-atoms of the 5-carboxylic group (forming a 4-membered chelate ring). Hydrogen bonding involving macrocyclic NH groups, both 2- and 5-carboxylic groups, perchlorate anions and water molecules gives rise to the formation of an infinite supramolecular network in the title compound's crystals.     

Peculiarities of the crystal structure and packing of the host and guest molecules in the [M(4-McPy)4(NCS)2]·0.67(4-McPy)·0.33 H2O Clathrates (M = Cu(II), Mn(II); 4-MePy = 4-Methylpyridine)

The crystal structures of the two clathrates with the composition [M(4-MePy)₄(NCS)₂]·0.67(4-McPy)·0.33 H₂O (M=Cu(II), Mn(II); 4-MePy=4-methylpyridine) have been determined. These compounds are trigonal, with the [M(4-MePy)₄(NCS)₂] host molecules being centrosymmetric. The parameters of the unit cells area = 27.365(7) and 27.738(6),c = 11.303(9) and 11.250(8) Å,V = 7325(2) and 7493(2) ų, space group R , R = 0.053 and 0.109 for M = Cu(II) and Mn(II), respectively. ForZ = 9d _calcd is equal to 1.271 and 1.225 g/cm³, andd _measd is equal to 1.252(2) and 1.213(2) g/cm³ for the Cu and Mn clathrates, respectively. The coordination environment of the metal atoms in these compounds is an irregular octahedron, while in the Mn compound these distortions are rather small (Mn-N_MePy 2.30, 2.34 Å, Mn-N_NCS 2.18 Å, and Cu-N_MePy 2.06 Å, Cu-N_NCS 1.98 Å and Cu-N_MePy 2.50 Å).The molecular packing in the structures is such that the channels of variable diameter are formed along the short cell dimension (the maximum diameter is 10 Å, the minimum being 6 Å) where the guest 4-MePy and H₂O molecules are placed.     

Structure of the neutral metal complex Pt(dddt)2

A neutral metal complex, [Pt(dddt)₂]° (1), has been obtained by oxidation of the [Pt(dddt)₂]^– anion with excess (Bu₄N)AuBr₄ in nitrobenzene. Crystallographic data for 1a=17.854(9) Å,b=18.409(9) Å,c=4.717(5) Å, =68.83(2)°, space group P2₁/n,Z=4,d _calc=2.55 g/cm³. In1 two independent centrosymmetric [Pt(dddt)₂]° molecules are packed in stacks that form layers parallel to the (110) plane. The molecules of1 in the layers have shortened S...S contacts 3.491(9) Å, and 3.594(10) Å. The average bond lengths Pt-S 2.242(7) Å, S-C 1.71(2) Å and C=C 1.40(3) Å, together with the square-planar coordination of Pt in PtS₄, suggest considerable conjugation in the metal cycles.Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 7, pp. 1207–1209, July, 1993.     

Neptunium(V) Perrhenate Complex with 1,10-Phenanthroline [(NpO2)(ReO4)(Phen)(H2O)2]: Crystal Structure and Absorption Spectra

Neptunium(V) perrhenate complex [(NpO₂)(ReO₄)(Phen)(H₂O)₂] was synthesized with 1,10-phenanthroline as a ligand. Its composition and structure were determined by X-ray diffraction analysis. The coordination polyhedron of the Np atom is a pentagonal bipyramid. The nearest surrounding of the neptunoyl ion includes the oxygen atom of the ReO₄ anion, two nitrogen atoms of phenanthroline, and the oxygen atoms of two water molecules. The crystals of the compound are monoclinic. The main crystallographic parameters are the following: space group P2₁/c, unit cell parameters a = 7.288(1) Å, b = 10.513(2) Å, c = 20.936(4) Å, = 96.939(5)°, Z = 4, V = 1592.2(5) ų. Absorption spectra of the compound in visible and IR regions are reported.     

Crystal and molecular structure of nitraminotetrazole and nitramino-1,2,4-triazole. IV. 5-nitraminotetrazole sodium salt sesquihydrate

The structure of 5-nitraminotetrazole sodium salt sesquihydrate was determined by X-ray diffraction. The crystals are monoclinic, space group P2₁/c;a = 3.551(1) Å, b = 21.834(4) Å, c = 9.075(2) Å; = 110.68(3)°; V = 658.3(2) ų; Z = 4; _calc = 1.807 g/cm³. The anion is planar and has an intramolecular hydrogen bond. The negative charge of the anion is localized on one of the oxygens of the nitro group. The sodium cation (c.n.6) is coordinated by three oxygen atoms of different anions and three oxygens of crystallization water. One of the crystallization water molecules is disordered in the unit cell. The anions are hydrogen-bonded with each other and with crystallization water molecules.Original Russian Text Copyright © 2004 by A. M. Astakhov, A. D. Vasiliev, M. S. Molokeev, L. A. Kruglyakova, A. M. Sirotinin, and R. S. StepanovTranslated from Zhurnal Strukturnoi Khimii, Vol. 45, No. 3, pp. 562–565, May–June 2004.     

Versatility in inclusion hosts. Unusual conformation in the crystal structure of thep-t-butylcalix[8]arene: Pyridine (1:8) clathrate

Crystal structure analysis proves that thep-t-butylcalix[8]arene host sits around a symmetry center in thePI crystal lattice. The triclinic cell parameters and calculated volume are:a = 10.034(2),b = 17.434(2),c = 18.321(2) Å, = 113.86(1)°, = 93.08(1)°, = 92.62(1)°,V = 2919(2) ų. ForZ = 1 and F.W. = 1834.6 the calculated density is 1.04 g/cm³. It is shown that the host macrocycle is in an open chairlike conformation and virtually leaves no cavity to be occupied by the guest molecule. Consequently the pyridine guest molecules are enclathrated through steric barriers into the crystal lattice, having only one of the guests in the asymmetric unit bound to the host. The open conformation of the host is facilitated by a break in the ring of O-O hydrogen bonds on the rim of the would-be calix. This structure also conveys essential information on the possible solution conformations of the host in pyridine.     

Interaction of Np(V) with N,N-Dimethylacetamide

A new Np(V) complex [(NpO₂)(NO₃)(DMAA)₂(H₂O)] was synthesized and its crystal structure was determined. Its absorption spectra were recorded in IR and near-IR regions. The unit cell parameters are a = 9.389(3) Å, b = 8.075(3) Å, c = 20.956(7) Å, = 92.53(3)°, space group P2₁/c, Z = 4, V = 1585.8(9) ų, R = 0.054, wR(F ²) = 0.170. The coordination polyhedron of the Np atom is a pentagonal bipyramid with the O atoms of two DMAA molecules, bidentate nitrate ion, and the water molecule in its equatorial plane.     

Preparation and x-ray structure determination of penta-and tetracyano-oxomolybdenum(IV) anions. The influence of water on their reactivity

Summary Several penta-and tetracyanooxomolybdenum(IV) anions have been synthesized containing different numbers of H₂O molecules, either coordinated or present as crystallisation molecules. The influence of these molecules on the reactivity of the complex, especially towards O₂, is discussed. Three compounds were characterized by x-ray structure determination. [Mo(O)(CN)₅(H₂O)₂(MeCN)₂][PPh₄]₄Cl belongs to triclinic space group P-1 witha=13.146(3) Å,b=16.944(5) Å,c=21.761(6) Å, =84.72(2)°, =87.15(2)° and =85.25(2)°. The volume of the unit cell is 4678(6)ų withz=2. The structure was refined to R=6.5%. [Mo(O)(CN)₄(H₂O)·6H₂O][PPh₄]₂ belongs to monoclinic space group P2₁/n witha=15.313(2)Å,b=19.983(3)Å,c=17.006(2)Å, =100.51(2)°. The volume of the unit cell is 5117(3)ų withz=4. The structure was refined to R=8.7%. [Mo(O)(CN)₄(MeCN)](PH₃)₂N]₂ belongs to triclinic space group P-1 witha=13.770(4)Å,b=16.292(5)Å,c=16.889(5)Å, =73.23(2)°, =72.02(2)° and =71.57(2)°. The volume of the unit cell is 3342(3)ų withz=2. The structure was refined to R=7.2%.     

Amiloride Conformation: The Effect of Different Crystalline Environments

The crystal structure of (3,5-diamino-6-chloro-pyrazine-2-carbonyl)-guanidine picrate has been determined with the use of X-ray diffraction method. The crystals are triclinic, space group PI with a = 10.2980(4) Å, b = 12.4322(4) Å, c = 14.4310(5) Å, = 66.317(2), = 70.077(2), = 72.462(2), Z = 2. The asymmetric unit consists of one amiloride cation, picrate anion, and three DMSO molecules from the solvent, two of which are disordered. The molecules of amiloride and picrate are almost planar. The guanidine group of amiloride is protonated and makes a kind of a salt bridge with phenolate and forms hydrogen bonds with ortho-nitro oxygen atoms of picrate. The pairs of amiloride cation–picrate anion, transformed by the inversion center and translated by 2 a and c, are mutually parallel and are connected by molecules of DMSO. The conformation of amiloride picrate is compared with those in other crystal structures.     

Crystal Structure of Cesium-Sodium Molybdate Dihydrate

Structure of CsNaMoO₄ · 2H₂O crystals formed in Cs₂MoO₄–Na₂MoO₄–H₂O system is determined by X-ray diffraction study. The unit cell parameters a = 6.379(2) Å, b = 8.631(2) Å, c = 13.670(2) Å, V = 752.6(3) ų, Z = 4, M = 351.87, (calcd) = 3.105 g/cm³, space group P2₁2₁2₁. The isle crystal structure is built of MoO₄ ^2-, Cs⁺, and Na⁺ ions. The Mo–O bond lengths lie within 1.756(2)–1.769(3) Å range. The OMoO bond angle is 109.45° on average. Three oxygen atoms of MoO₄ ^2- anion are involved in hydrogen bonds with water molecules., while the fourth O atom participates in the formation of Na polyhedra only. The octahedral environment of Cs⁺ ions is formed by oxygen atoms of MoO₄ ^2- anions, without participation of water molecules. The structure contains two crystallographically independent water molecules, whose tetrahedral coordination consists of two Na⁺ ions and two MoO₄ ^2- anions.     

Polymorphism of Crystalline Inclusion Complexes and Unsolvated Hosts. Part 8

Crystallization of cyclotriveratrylene (CTV) from solutions in acetone at 40°C gave a new 4:1 host-guest complex instead of the conventional 2:1 clathrate (-phase) whose X-ray crystal structure was determined. Data for 2(C₂₇H₃₀O₆) · 0.5(CO(CH₃)₂): monoclinic, P2₁/c, a = 18.942(4), b = 24.697(5), c = 10.508(2) Å, = 91.10(2)°, V = 4915(2) ų, Z = 8, D _x = 1.257 g/cm³, T = 293 K, R = 0.077 (for 2694 reflections). One of the two crystallographically independent CTV molecules (molecule A) is stacked into columns characteristic of the CTV - or -phase complexes. Molecules B face each other enclathrating inside around the inversion center disordered acetone molecules giving rise to the molecular capsule. The acetone molecule is H-bonded simultaneously to both host molecules by C(H₂)--H ··· O type bonds forming centrosymmetric dimers. Dimers are incorporated together with two A molecules into centrosymmetric units also by C(H₂)--H ··· O type H-bonds. Packing of these units gives rise to the crystal structure of the clathrate.     

The crystal structure of tetraphenylarsonium tricyanooxopyridine-2-carboxylatotungstate(IV) dihydrate

Summary The structure of (AsPh₄)₂[WO(CN)₃(Pic)] · 2H₂O has been determined from three dimensional x-ray data. The cell dimensions are:a=17.699(8),b=13.546(6),c= 13.590(6) Å, =117.39(8), = 71.54(7) and = 115.04(8)°, space group P¯1, Z = 2, The structure was solved from 5279 observed reflections. The anisotropic refinement converged to R = 0.060.The [WO(CN)₃(Pic)]^2–-ion is a distorted octahedron. The structure indicates that the aqua group in [WO(CN)₄(H₂O)]^2– was displaced by an oxygen atom of the carboxylate of 2-picolinate, while a cyanide ligand was substituted by the pyridine nitrogen atom. Themer-arrangement of the three cyanide ligands has two normaltrans W-C_av = 2.17(2) Å bond distances and a significant shorter W-C = 2.042(18) Å bond trans to the W-N [2.188(18) Å] bond. The W=O and W-O bond lengths are 1.676(9)Å and 2.171 Å, respectively.     

Palladium Clusters Pd4(SEt)4(OAc)4and Pd6(SEt)12: Structure and Properties

Palladium clusters Pd₄(SEt)₄(OAc)₄(I) and Pd₆(SEt)₁₂(II) were synthesized and studied. Their structure was determined by X-ray diffraction analysis. For I, a= 9.774(2) Å, b= 10.821(2) Å, c= 13.061(3) Å, = 92.88(3)°, V= 1379.6(5) ų, (calcd.) = 2.182 g/cm³, space group P2₁/n, Z= 4, N _ref= 1558, and R= 0.031; for II, a= 10.581(1) Å, b= 10.584(2) Å, c= 11.478(2) Å, = 101.62(1)°, = 104.95(1)°, = 106.74(1)°, V= 1135.2(4) ų, (calcd) = 2.007 g/cm³, space group P1, Z= 1, N _ref= 2828, and R= 0.022. In cluster I, four Pd atoms form a planar cycle. The neighboring palladium atoms are bound by two acetate or by two mercaptide bridges, the Pd···Pd distances being 3.036–3.195 Å. In cluster II, Pd atoms form a planar six-membered cycle with Pd···Pd distances of 3.083–3.127 Å. The neighboring palladium atoms are bound by two mercaptide bridges. The formation of analogous clusters in solution was confirmed by IR spectroscopy.