Tuning solid-state calix[n]arene supramolecular assemblies using

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Tuning solid-state calix[n]arene supramolecular assemblies using phenanthroline as the guest molecule Barbara Lesniewska, Anthony W. Coleman, Florent Perret, and Kinga Suwinska Cryst. Growth Des., Just Accepted Manuscript • DOI: 10.1021/acs.cgd.8b01629 • Publication Date (Web): 08 Feb 2019 Downloaded from http://pubs.acs.org on February 10, 2019

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Crystal Growth & Design

Tuning solid-state calix[n]arene supramolecular assemblies using phenanthroline as the guest molecule Barbara Leśniewska,1* Anthony W. Coleman,2 Florent Perret,3 and Kinga Suwińska 4,5*. 1Institute

2LMI,

of Physical Chemistry, Polish Academy of Sciences, Kasprzaka 44/52, 01-224 Warsaw

Université Lyon 1, CNRS UMR 5615, 43 bvd 11 novembre, 69622,Villeurbanne, France

3ICBMS,

Université Lyon 1, CNRS UMR 5246, 43 bvd 11 novembre, 69622, Villeurbanne,

France 4Faculty

of Mathematics and Natural Sciences, Cardinal Stefan Wyszynski University,

Wóycickiego 1/3, 01-938 Warsaw 5A.

M. Butlerov Institute of Chemistry, Kazan Federal University, Kremlevskaya ul. 18, Kazan,

420008, Russia

KEYWORDS calix[n]arene, phenanthroline, co-crystal, inclusion compound, organic salts, inclusion polymer

ACS Paragon Plus Environment

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ABSTRACT

Of the available ligands for the study of molecular recognition by para-sulphonato-calix[n]arene receptors phenanthroline is proving to a far more versatile moiety than it would be initially expected. Interactions with two anionic host molecules: para-sulphonato-calix[4]arene and parasulphonato-calix[8]arene have been previously examined in depth and described. In this paper further structural studies concerning supramolecular self-assembly species of unsubstituted calix[6]arene, para-sulphonato-calix[6]arene, para-sulphonato-calix[4]arene and 25,27-Odi(carboxymethoxy)-calix[4]arene with phenanthroline are reported. Structures of crystalline host-guest complexes were determined by means of X-ray diffraction. Diversity of the chemical make up of the structures is observed, four structures are co-crystals and the other four are organic salts. In the packing motifs columnar systems are the commonest among those observed.

INTRODUCTION Calixarenes are the most important organic macrocyclic receptors and building blocks in supramolecular chemistry1 and indeed in supramolecular biochemistry,2–5 and among the most important in supramolecular pharmaceutical science.4,5 The calix[n]arene molecular skeleton consists of a series of phenol rings linked by methylene groups, variations on the theme may have different bridging units and variable numbers of phenolic hydroxyl functions.6 They can be molecular containers or host molecules because of their flexible and geometrically variable interior cavity which is large enough to accommodate one or more smaller molecules.7–12 The cavity is accessible through the π-electron rich aromatic rings or the hydroxyl groups. The formation of the host-guest complex is stabilized by forces such as ionic interactions, hydrogen bonding, π‒π interactions, hydrophobic forces and van der Waals contact energies.


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The basic calix[n]arene molecules can be made more complex by modifying the aromatic rings at the para position and/or substituting hydrogen atoms of the hydroxyl groups with a variety of functional groups, e.g., adamantyl,13 phosphonic acid,14 carboxylic acid,15 sulphonic acid,16 alkyl,17 acyl,18 ester, ether, amino,19 nitro etc. The goal of the functionalization of calix[n]arene molecules is, among others, changing their solubility in a specific solvent, or changing the selectivity and the stability of their complexes formed with other molecules. They may act as ionic or neutral receptors depending on the way they are modified. Calix[n]arenes have the ability to form various supramolecular connections and architectures such as dimers, columns, bilayers, molecular capsules, polymers stabilized by hydrogen bonds, one, two or threedimensional coordination polymers, “ferris wheel” and “Russian doll” motifs, packages having the shape of a helix (“helical arrays”), channels filled with guest and/or solvent molecules, twoor three-dimensional porous materials and also nanometer diameters balls or tubes.7–12,20 Of the vast range of guest molecules available in supramolecular chemistry, 1,10phenanthroline offers rigidity, planarity, aromaticity, basicity and chelating capabilities. It also has unique photochemical and electronic properties.21–24 It can act as a chemical nuclease and as a therapeutic agent due to its ability to bind or interact with the DNA biomacromolecule.25 1,10Phenanthroline, itself, is not a subject to conformational changes but it can induce conformational changes of the flexible molecules with which it forms complexes.26 The specific molecular recognition properties calixarenes make them interesting and important members of the field of host-guest chemistry. They have a number of potential applications in areas such as, separation and purification technologies, analytical and sensors devices, catalysis, drug delivery and are themselves Active Pharmaceuticals Ingredients (APIs).27,28


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It is, thus, of interest to investigate the interaction between 1,10-phenanthroline and the various anionic calix[n]arenes in order to gain insight into the biological and therapeutical properties of the two systems.23–30 Such structural information may aid in the interpretation of the biological results but is unlikely at the current time to allow predictions on binding to biological systems to be made. In this work, the ability to form solid-state host-guest supramolecular complexes with 1,10phenanthroline (Phen) is examined with regard to 25,27-O-di(carboxymethoxy)calix[4]arene (C4diCA), para-sulphonato-calix[4]arene (C4S), para-sulphonato-calix[6]arene (C6S) and calix[6]arene (C6).

Scheme

1.

Structural

formulae:

(a)

1,10-phenanthroline

(Phen);

(b)

25,27-O-

di(carboxymethoxy)-calix[4]arene (C4diCA); (c) calix[6]arene (C6); (d) para-sulphonatocalix[4]arene (C4S); (e) para-sulphonato-calix[6]arene (C6S). EXPERIMENTAL Synthesis of calixarenes


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25,27-O-di(carboxymethoxy)calix[4]arene was synthetized using the method described by Rudzevich et al.29 para-Sulphonato-calix[n]arenes were synthetized by the method previously used for para-sulphonato-calix[4]arene by Coleman.30 The purity of the synthesized molecules was verified using high resolution mass spectrometry. Calix[6]arene and 1,10-phenanthroline were purchased from TCI Chemicals and used without further purification. Crystal growth In each case suitable crystals for X-ray diffraction were grown by slow evaporation during several days. The crystallization experiments were carried out at 20 °C in sealed tubes. Synthesis of complexes 1 and 2: 4 equiv. of Phen were added into 1 mL of a 100 mg mL-1 solution of C4diCA in ethanol-tetrahydrofuran 1:1 mixture and C4S in water for 1 and 2, respectively, and gently heated in a water bath to completely dissolve all substrates. The resulting solutions were then allowed to crystallize. Synthesis of complexes 3 and 4: 6 equiv. of Phen were dissolved in 1 mL of a 100 mg mL-1 solution of C6S in water or water-ethanol 1:1 mixture for 3 and 4, respectively, and gently heated in a water bath to completely dissolve all substrates. The resulting solutions were then allowed to crystallize. Synthesis of complex 5: 3 equiv. of Phen and 3 equiv. of Mg(NO3)2·6H2O were dissolved in 1 mL of a 100 mg mL-1 solution of C6S in water and gently heated in a water bath to completely dissolve all substrates. The resulting solution was then allowed to crystallize.


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Synthesis of complexes 6, 7 and 8: 6 equiv. of Phen dissolved in ethanol was layered on 1 mL of a 100 mg mL-1 solution of C6 in dichloromethane-ethanol 6:1 mixture, tetrahydrofuranethanol 6:1 mixture or acetone for 6, 7 and 8, respectively, and put upon gentle heating. X-ray structure determination The X-ray data were collected at 100 K on a Nonius KappaAPEXII diffractometer using MoKα radiation for complexes 1, 2, 3 and 4, and on an Agilent SuperNova diffractometer equipped with a CuKα micro-focus X-ray source for all the remaining samples (5–8). Structures were solved by direct methods with SHELXS-9731 and refined against F2 with full-matrix leastsquares using SHELXL-201832. Hydrogen atoms were calculated at their idealized positions and were refined as riding atoms with isotropic thermal parameters based upon the corresponding bonding atom (Uiso = 1.2Ueq, Uiso = 1.5Ueq for CH3 and OH hydrogens). Hydrogen atoms of methyl and hydroxyl groups were refined in geometric positions for which the calculated sum of the electron density is the highest (rotating group refinement). Where possible hydrogen atoms of amino groups and water molecules were located on Fourier difference maps and refined with positional parameters. Due to the high degree of disorder in complexes 2 and 4 as well as very poor quality of the crystals, the R values for these structures are high but we decided to report these data for their importance to the overall discussion on the influence of the phenanthroline as a guest molecule on the solid state complexes formation. Crystal data and details of structure refinements for the studied complexes are given in Table. 1. Crystal structures are deposited with the Cambridge Crystallographic Data Centre as 1437838, 1437839, 1875582-1875587.


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Table 1. Crystal data and details of structure refinements for complexes 1–4. Compound Molecular formula Formula weight Temperature, K Wavelength, Å Space group a, Å b, Å c, Å α, ° β, ° γ, ° Volume, Å3 Z Density (calculated) g·cm-3 Absorption coefficient, mm-1 Crystal size, mm Ɵ range for data collection,° Reflections collected Independent reflections Data/restraints/parameters Goodness-of-fit on F2 Final R indices [I > 2σ(I)] R indices (all data)

Complex 1 C32H28O8·C12H8N2·C4H8O 792.85 100.0(2) 0.71073 P212121 10.3613(4) 16.5342(7) 22.746(1),

3896.8(3) 4 1.351 0.094 0.43×0.18×0.10 2.93–24.72 23381 3755 [Rint = 0.158] 3738/91/587 1.04 R = 0.077, wR = 0.148 R = 0.127, wR = 0.170

Complex 2

Complex 3

Complex 4

2C28H18O16S46·12C12H9N2+·29.5H2O 4247.39 100.0(2) 0.71073 P 19.3724(3), 20.0094(3), 30.4618(5) 106.0352(5) 92.7187(6) 111.865(1)° 10381.5(3) 2 1.319 0.176 0.26×0.15×0.11 2.82–25.35 127741 37586 [Rint = 0.127] 37497/2332/3523 1.03 R = 0.149, wR = 0.356 R = 0.221, wR = 0.393

C42H30O24S66⎻·6C12H9N2+ ·22H2O 2594.64 100.0(2) 0.71073 P 11.5836(2) 15.0460(3), 17.9652(4) 80.7820(8) 74.6046(8) 84.9837(7) 2976.4(1) 1 1.447 0.212 0.30×0.28×0.20 2.82–25.68 49805 11280 [Rint = 0.167] 11269/129/977 1.14 R = 0.080, wR = 0.192 R = 0.109, wR = 0.206

C42H30O24S66⎻·6C12H9N2+ ·18H2O 2522.58 100.0(2) 0.71073 P 11.2240(2) 13.8500(3) 19.3940(5) 77.927(1) 75.543(1) 87.762(1) 2854.5(1) 1 1.467 0.216 0.15×0.13×0.08 2.92–26.31 43569 11552 [Rint = 0.105] 11551/2507/1316 1.04 R = 0.156, wR = 0.361 R = 0.235, wR = 0.405


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Compound Molecular formula Formula weight Temperature, K Wavelength, Å Space group a, Å b, Å c, Å α, ° β, ° γ, ° Volume, Å3 Z Density (calculated) g·cm-3 Absorption coefficient, mm-1 Crystal size, mm Ɵ range for data collection,° Reflections collected Independent reflections Data/restraints/parameters Goodness-of-fit on F2 Final R indices [I > 2σ(I)] R indices (all data)

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Complex 5

Complex 6

Complex 7

Complex 8

C42H30O24S66⎻·4C12H9N2+ ·Mg[H2O]62+·17H2O 2274.55 100.0(2) 1.5418 P 12.7945(3) 12.8361(3) 15.4558(3) 98.207(2) 95.114(2) 92.078(2) 2499.2(1) 1 1.511 2.211 0.50×0.20×0.04 6.23–68.25 19479 9131 [Rint = 0.020] 9094/22/769 1.03 R = 0.037, wR = 0.097 R = 0.041, wR = 0.100

C42H36O6·1.5C12H8N2 ·0.5C2H5OH 930.05 100.0(2) 1.5418 P 12.3918(8), 13.5648(9) 15.828(1) 71.012(6) 78.765(6) 70.081(6) 2354.7(3) 2 1.312 0.681 0.50×0.50×0.20 5.99–68.25 16020 8590 [Rint = 0.022] 8590/7/697 1.03 R = 0.052, wR = 0.129 R = 0.064, wR = 0.136

C42H36O6·1.5C12H8N2 ·0.5C3H6O 936.06 100.0(2) 1.5418 P 12.5273(3) 13.5042(3), 15.7764(4) 71.697(2) 78.705(2) 70.330(2) 2373.9(1) 2 1.310 0.679 0.60×0.60×0.60 6.01–65.09 37375 8074 [Rint = 0.038] 8045/145/744 1.09 R = 0.073, wR = 0.176 R = 0.074, wR = 0.176

C42H36O6·1.25C12H8N2 ·0.5C2H6O·0.5C4H8O 921.05 100.0(2) 1.5418 P 12.4255(7) 13.2184(7) 16.0378(9) 70.823(5), 78.500(5) 71.121(5) 2341.3(2) 2 1.306 0.682 0.20×0.10×0.10 6.11–70.07 15106 8809 [Rint = 0.031] 8792/190/775 1.02 R = 0.065, wR = 0.186 R = 0.073, wR = 0.196


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RESULTS AND DISCUSSION Complex 1 Crystals of complex 1 were obtained from the methanol-tetrahydrofuran crystallization medium. The asymmetric part of the unit cell (Figure 1) contains one fully protonated molecule of C4diCA, one phenanthroline (Phen) and one disordered tetrahydrofuran molecule with site occupancy factors of 0.50. Angles C‒N‒C in molecule are 117.9(6) and 118.7(6)° indicating that the guest molecule is not protonated. Hydrogen atoms on O3B and O2D atoms belonging to the carboxylic groups of C4diCA were located on the Fourier map.

Figure 1. The asymmetric unit of complex 1. The C4diCA molecule adopts the cone conformation which is stabilized by two intramolecular O‒H···O hydrogen bonds [2.689(7) and 2.782(8) Å] between phenolic hydroxyl groups and the other oxygen atoms belonging to the substituents at the lower rim of C4diCA. The dihedral angles formed by the opposite phenolic rings of calixarene are 35.0(2)° between moieties with carboxylic functions and 101.2(2)° between non functionalized moieties. Phen molecule is slantwise included into the molecular cavity of the host. Dihedral angle between the plane of Phen molecule and the plane defined by four carbon atoms of methylene groups (reference


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plane) of C4diCA and the depth of inclusion of Phen within the cone of C4diCA measured as the distance between the centroid of included phenanthroline ring and the reference plane of C4diCA are given in Table 2. The inclusion is stabilized by three C‒H···π hydrogen bonds [3.521(7), 3.270(8), 3.336(7) Å] and one π‒π interaction [3.658(3) Å] between Phen and aromatic ring B of C4diCA (Figure 1). The nitrogen atoms of the included Phen molecule accept two O‒H···N hydrogen bonds [2.676(8), 2.651(7) Å] from hydroxyl oxygen atoms belonging to the carboxylic substituents of two neighboring calixarenes. Additionally, guest carbon atoms C7X, C8X and C12X are involved in weak C‒H···O interactions to the close C4diCA molecule. This mode of interactions affects the geometry of Phen molecule which deviates significantly from planarity (Figure 2).

Figure 2. Phen molecule located in molecular cavity of one calixarene and distorted by two opposite O‒H···N hydrogen bonds. The inclusion complex interacts by C‒H···π [3.804(9) Å] hydrogen bonding with the adjacent complex related by two-fold screw axis running down the [100] crystallographic direction. Consequently, a 1D inclusion polymer based on weak intermolecular interactions is formed resulting in a herring bone like arrangement of the Phen molecules (Figure 3). So far, this is the only example of inclusion of Phen molecule within the molecular cavity of a calix[n]arene


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unsubstituted at upper rim and a unique arrangement of Phen molecules in complexes with calixtype molecules in general, with the exception of C6/Phen reported later in this article, and calix[4]arenes in particular (the only known complex of Phen with unsubstituted at upper rim calix[4]arene is that with calix[4]arene dihydroxyphosphonic acid [IYENEF]33 where the dimer formation (self-inclusion) by two host molecules is present and finally a co-crystal was obtained). Formation of dimeric capsular arrangement with two Phen molecules oriented in parallel between two calix[4]arene molecules is common is (e.g. APAPAJ26) and was observed in case of organic salts formed by para-sulphonato-calix[4]arenes.34-38

Figure 3. 1D inclusion polymer linked via C‒H···π interactions between Phen guest molecules (top) and arrangement of Phen and THF molecules in the channels showing weak interactions between them (bottom).


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Calixarene molecules form one dimensional chains running in the [010] crystallographic direction. They are stabilized by two C‒H···O interactions [3.292(9) and 3.572(2) Å] between carbon atoms belonging to the aromatic rings of calixarene and oxygen atoms of respectively, carboxylic or phenolic hydroxyl groups of neighboring C4diCA molecule. The chains are next arranged in layers perpendicular to the [001] crystallographic direction (Figure 4). Additionally, one weak C‒H···O hydrogen bond [3.38(2) Å] is observed between carbon atom belonging to aromatic ring of the host molecule and oxygen atom of tetrahydrofuran which is trapped within the crystal lattice of the complex (shown in Figure 1). Selected interactions present in the structure of complex 1 are listed in the Table S1 (Supporting Information).

Figure 4. One dimensional calixarene chains formed by C‒H···O interactions along [010] crystallographic direction and view along [001] axis.


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Figure 5. Crystal packing of complex 1 showing distorted hexagonal channels filled with guest and solvent molecules, view along [100] crystallographic direction. C4diCA, Phen and tetrahydrofuran molecules are marked in green, blue and red, respectively. The crystal packing of molecules present in the complex 1 is a channel-type packing (Figure 5). Calixarene layers are arranged in such a way that down [100] crystallographic direction distorted hexagonal channels occupied by phenanthroline and tetrahydrofuran molecules are formed. 25,27-O-di(carboxymethoxy)-calix[4]arene arrangements reported so far are spectacular helical aquatubes in its hydrate [CEFWAM],39 polymeric cages with a solvent trapped inside them in its acetone solvate [UFIQEG]40 and layered in the complex with chlorhexidine [WODGIG].41 In these structures as well as in the complex of calix[4]arene dihydroxyphosphonic acid with Phen33 – calixarene molecules form, as mentioned above, interdigitated dimeric units. In the reported here complex 1 this mode of self-assembly is prevented by inclusion of Phen molecule inside the molecular cavity of C4diCA and calixarene chains formation is observed instead of dimers. Similar breaking of the interdigitated dimeric


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structure was reported for the inclusion complexes of calix[4]arene dihydroxyphosphonic acid with piroxicam and 9-aminoacridine.14 Complex 2 Crystals of complex 2 were obtained from a methanol-water crystallization medium. The asymmetric part of the unit cell (Figure 6) contains two crystallographically distinct C4S anions, twelve Phen cations (six of them are disordered) and 29.5 water molecules which are mostly disordered.

Figure 6. The asymmetric unit of complex 2. One of the host anions contains two disordered sulfonate groups and the second only one. The high degree of disorder in the structure does not allow to estimate the real protonation state. Based on the position of the water molecules near the nitrogen atoms of Phen at the distances corresponding to the hydrogen bond lengths it was assumed that Phen cations are monoprotonated and hence two phenolic groups of the C4S are deprotonated. Deprotonation is additionally confirmed by short oxygen–oxygen distances between the phenolic groups [2.441(8), 2.526(7), 2.552(5) Å for one and 2.475(9), 2.525(9), 2.597(8) Å for the second C4S


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molecule] indicating the formation of charge enhanced hydrogen bonding. The dihedral angles formed by the opposite phenolic rings of the C4S are 70.6(2), 88.3(2)° and 67.6(2), 87.7(3)°, respectively for the two symmetrically independent C4S molecules. Dihedral angle between the plane of Phen molecule and the reference plane of C4S and the depth of inclusion of Phen within the cone of C4S are given in Table 2. The structural motifs and crystal packing are very similar to those previously reported by us APANUB structure (C4S/Phen complex).26 In the structure of complex 2 a pseudo symmetry was found indicating that 2 is a superstructure to the APANUB structure. The unit cell of complex 2 is about twice as large as in APANUB (a ≈ a, b ≈ c, c ≈ 2b). Complex 3 Crystals of the complex 3 were obtained from a tetrahydrofuran-water crystallization medium. The pseudo-polymorphic complex of para-sulphonato-calix[6]arene and 1,10-phenanthroline have been previously reported as TIKVIT.42 In this case the crystallization was carried out from an aqueous solution in the presence of HCl and crystal structure was determined at 113 K.

a

b


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Figure 7. Complex 3: (a) the asymmetric unit (part of the molecule marked in fuchsia is symmetry related); (b) an inclusion 1:2 host-guest complex formed by the C6S anion and two cations of 1,10-phenanthroline. The asymmetric part of the unit cell of the 3 complex contains half of the C6S hexaanion in which one sulfonate group is disordered, three monoprotonated Phen cations and 11 water molecules, some of which are disordered (Figure 7a). For comparison, the asymmetric part of the unit cell of the TIKVIT contains two halves of C6S anion, four monoprotonated Phen cations, and 21 water molecules. In TIKVIT as well as in the structure reported herein, the C6S anion adopts the centrosymmetric inverted double partial cone conformation. Such a conformation provides the creation of two molecular cavities, each able to accommodate one phenanthroline cation and, consequently, an inclusion 1:2 host-guest complex is formed (Figure 7b). The geometry of the host-guest complex in 3 is very similar, though not identical, to that found in TIKVIT. The Phen cation is not located parallel to the axis of the partial cone, as was observed in the case of para-sulphonato-calix[4]arene,26,43 but is tilted within the cavity (a similar arrangement of Phen guest was also observed in the case of the para-sulphonato-calix[8]arene host and in TIKVIT).42,44 Dihedral angles between the plane of Phen molecule and the reference plane of C6S both in complex 3 and TIKVIT, and the depths of inclusion of Phen within the cones of C6S and TIKVIT are given in Table 2 [in case of six-membered calixarenes the reference plane is defined by four methylene carbons of the partial cone(s)]. In the present complex 3, the inclusion of the phenanthroline cation is stabilized by the host-guest interactions such as π‒π 3.650 (2) Å between the protonated ring of Phen X and the aromatic ring A of calixarene, and C‒H···π interactions between the carbon atom belonging to the methylene group of the macrocycle and the central ring of Phen X and between the carbon atoms of the central


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and protonated rings of Phen X and aromatic rings B and C of calixarene [3.329(4), 3.628(4), 3.572(5) Å, respectively]. The protonated nitrogen atom of the Phen X cation located within the macrocyclic cavity is hydrogen bonded to the oxygen atom of a sulphonate group of an adjacent calixarene [N‒H···O: 2.734(4) Å]. Additionally, Phen X ions form dimers with Phen X ions belonging to the neighboring centrosymmetrically located inclusion compounds through π‒π interactions (Figure 8c). Phen X cations in the dimer are distanced by 3.36 Å. Dimers of Phen X together with the C6S anions form an alternate ceaseless columnar array along the [100] crystallographic axis (Figure 8a and b). The height (H – measured as the distance between the centroids of C6S) of the single unit in the described inclusion polymer is identical to a parameter of the unit cell and it is about 0.28 Å shorter than in the analogous system present in the TIKVIT crystal (see Table 2).

a

b

c


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Figure 8. Columnar arrangement formed by C6S/Phen inclusion complexes: (a) the stick model; (b) the spacefill model; (c) Phen X dimer in the crystal of complex 3. The remaining two Phen cations (Y and Z) which are located outside the macrocyclic cavities form π-stacking tetramers intercalated between two C6S anions (Figure 9). The distance between Phen Z cations in the tetramer is 3.44 Å and estimated distance between Phen Z and Phen Y cations is 3.69 Å.

Figure 9. The phenanthroline tetramer intercalated between two C6S anions in the crystal of complex 3. Tetramers, which are isolated by water molecules, are located between the C6S/Phen columns and form (together with water molecules) separate columns parallel to these formed by C6S/Phen visible in Figure 10a and Figure S1 (Supporting Information). External cations of Phen Y and Z involved in tetramer formation interact with calixarenes by π-stacking face-to-face type of 3.467(3) Å between rings of Phen Y and the aromatic ring B of calixarene and π-stacking face-to-edge type of 3.578(2) Å between unprotonated ring of Phen Y and an aromatic ring C of C6S situated in neighboring columns. There is also C‒H···π interaction of 3.609(4) Å between the carbon atom belonging to the methylene group of the


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macrocycle and the unprotonated ring of Phen Y and several C‒H···O interactions between Phen Z and Y and sulphonate oxygen atoms of the host anions. Selected interactions present in the structure of complex 3 are listed in the Table S3 (Supporting Information). In comparison, in the TIKVIT crystal there are two crystallographically independent Phen dimers, instead of tetramers, intercalated between two independent calixarene anions. In both structures, C6S anions do not interact directly with each other (Figure 10a). The closest distances between neighboring calixarenes from the adjacent columns in 3 are longer than 4.2 Å. Regarding the columns formed by C4S/Phen inclusion complexes and Phen tetramers as supramolecular building blocks the resulting crystal of 3 is a channel-type structure (Figure 10). Zig-zag channels extending in the direction of [100] crystallographic are filled with disordered water molecules which are located in pseudo-cavities with dimensions 7×8×11 Å and are connected with throats of 5×7 Å (Figure S2 in Supporting Information and Figure 11a). The walls of these channels are formed by aromatic rings of Phen Y and Z cations and hydrophilic negatively charged sulphonate groups of C6S.

a

b


19


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Figure 10. Channels in the crystal of complex 3, view along the [100] crystallographic axis: (a) the stick model; (b) the spacefill model in which water molecules are omitted to show the channels. In the structure a second set of channels running down [001] crystallographic directions is present. This channels are formed by alternately connected small (5×5×5 Å) and large (7×7×12 Å) cavities. The interchannel throats in this case are very narrow and do not allow the water molecules to move between the cavities. The water molecules within this channels are mostly ordered. The walls of these cages are formed by hydrophilic negatively charged sulphonate groups of C6S and rings of Phen Y and Z ions (both non heterocyclic and heterocyclic protonated and unprotonated parts).

a

b


20

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Figure 11. Water channels in crystals of C6S-Phen complexes: (a) channels in the crystal of complex 3, view along the [010] (top) and [001] (bottom) crystallographic axes; (b) channels in the TIKVIT structure, view along the [001] crystallographic axis, the channels run down the [110] crystallographic axis. All molecules except water molecules are omitted from the packing. Mercury program was used to visualize the solvent accessible channels.45 Both sets of channels are connected via narrow throats and finally, a 3D channel network is formed (Figure 10 and Figure 11). For comparison, in the TIKVIT, similar columnar and close to layered crystal packing is observed. The columns in this case are packed closer because they are separated by Phen dimers instead of tetramers present in 3. One dimensional water channels in this structure are parallel to the [110] crystallographic direction and they are presented in Figure 11b.The total calculated solvent accessible volume in the crystal of complex 3 is 564 Å3 and 19% of the unit cell volume, this space is marked in yellow in Figure 13, and is the same as in the TIKVIT (19%, 936 Å3). Complex 4 Crystals of the complex 4 were obtained independently from ethanol-water and methanolwater solutions. The asymmetric part of the unit cell (Figure 12) contains half of the C6S hexaanion, three monoprotonated Phen cations and 9 water molecules of which only two are ordered.


21


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Figure 12. The asymmetric unit of complex 4. Part of molecule marked in fuchsia is symmetry related. The crystal of complex 4 is pseudo isostructural with 3. The differences between these two structures is the number of water molecules in the asymmetric unit (9 in 4 vs. 11 in 3), disorder of all sulphonate groups in the C6S anion and disorder of all Phen cations. Phenanthroline cations V/X and W/Y were refined in two positions, with s.o.f. = 0.5 each, while the third U/Z/T Phen ion occupies three different positions rotated in the plane with s.o.f. = 0.4, 0.3 and 0.3 assigned to them (Figure 13).

a

b

c

Figure 13. Disordered phenanthroline cations in crystal of complex 4: (a) V/X cation (X – yellow); (b) W/Y cation (Y – blue); (c) U/Z/T cation (Z – green, T – orange).


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The C6S anion adopts the centrosymmetric inverted double partial cone conformation, like in 3 and TIKVIT structures, and similar inclusion complex is formed (Figure 7b). Comparison of conformations of the C6S anions and C6S/Phen inclusion complexes in 3 and 4 is shown in Figure 15. In the crystal of 4, the dihedral angle between the plane of Phen molecule and the reference plane of C6S and the depth of inclusion of Phen within the cone of C6S are given in Table 2. Interactions of C6S anions and Phen cations are analogous to these observed in complex 3. Selected interactions present in the structure of complex 4 are listed in the Table S4 (Supporting Information). C6S anions do not interact directly with each other. The closest distances between neighboring calixarenes from the adjacent columns in 4 are longer than 4.3 Å. The C6S ions and Phen V/X guest molecules in 4 are arranged in the same columnar way as in 3 structure. The distance between planes of Phen V/X cations in the dimer is 3.44 Å. The height of the single unit in the described inclusion polymer is identical to a parameter of the unit cell and it is about 0.36 Å shorter than the capsule observed in 3 (Figure 8, Table 2). Similarly to the previous structure, columnar and layered crystal packing is observed here but, contrary to the 3 and TIKVIT, the water molecules occupy cavities present in the crystal, not channels. Two types of cavities of approx. dimensions 9×5×6 Å and 16×5×5 Å may be distinguished. The second one is in form of Z shape. The calculated volume accessible for water molecules is smaller in this case and is 6.2 % (176.3 Å3) of the unit cell volume. This is caused by the fact that the disordered Phen guest cations occupy more space in the crystal compared with the ordered ones in 3. Complex 5


23


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Crystals of the complex 5 were obtained from aqueous solution. The asymmetric part of the unit cell contains half of the C6S hexaanion, two monoprotonated Phen cations, half of hexahydrated magnesium ion and 8.5 water molecules, two of which are disordered (Figure 14).

Figure 14. The asymmetric unit of the complex 5. Part of molecule marked in fuchsia is symmetry related.

Figure 15. The superposition of five C6S/Phen inclusion complexes showing the similarities in conformation of C6S anions and in inclusions modes: 3 – yellow, 4 – red, 5 – green), TIKVIT – grey and cyan (two crystallographically independent complexes).


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The C6S anion adopts again the centrosymmetric inverted double partial cone conformation and a similar 1:2 (host:guest) inclusion complex with Phen is formed (Figure 7b). Comparison of the conformations of the C6S anions and the C6S/Phen inclusion complexes in 5, 3, 4 and TIKVIT is shown in Figure 15. Dihedral angle between the plane of Phen molecule and the reference plane of C6S and the depth of inclusion of Phen within the cone of C6S are given in Table 2. The inclusion of Phen Y cation is stabilized by π‒π interactions of 3.601(1) Å – a mean distance between unprotonated ring of Phen Y and the aromatic ring A of calixarene, and by the C‒H···π interactions: 3.476(2), 3.713(2), 3.720(2) Å between the carbon atom belonging to the methylene group of the macrocycle and the central ring of Phen Y, and between the carbon atoms placed in the central ring of Phen Y and aromatic rings B and C of calixarene, respectively. Additionally there is C‒H···O interaction of 3.090(2) Å between the carbon atom belonging to the unprotonated ring of Phen Y guest and sulphonate oxygen atom of ring A of the host anion. The protonated nitrogen atom of Phen Y cation located in the macrocyclic cavity forms a strong N‒H···O [2.701(2) Å] hydrogen bond to one of the water molecules. Phen Y cations located inside the host cavities form dimers through π‒π interactions between Phen Y ions belonging to the neighbouring centrosymmetrically located inclusion complexes with the Phen Y cations separated by 3.306(3) Å (Figure 8c). Along the [010] crystallographic axis similar columnar arrangement is observed as in 3, 4 and TIKVIT (Figure 8a and b). The height of the single unit in the described inclusion polymer is identical to b parameter of the unit cell and is the longest one observed in the discussed structures (Table 2).


25


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b

Figure 16. Intercalation of uncomplexed Phen dimers in the crystal of complex 5: (a) Phen X dimer intercalated between two C6S anions; (b) Phen X dimer covered from the top and bottom by hexaaqua magnesium ions. Cations of Phen X which are located outside of the macrocyclic cavities form π-stacking dimers, with interplanar distance of 3.386(1) Å, and are intercalated between two anions (Figure 16a). The Phen X dimers interact with calixarenes by N‒H···O hydrogen bond [2.701(2) Å] between protonated nitrogen atom of Phen X and sulphonate oxygen atom of C6S, by π‒stacking between rings of Phen X and the aromatic ring C of calixarene (the mean distance 3.314(3) Å), by C‒H···π interaction of 3.598(2) and 3.673(2) Å between the carbon atoms belonging to the unprotonated and protonated Phen X rings and aromatic rings of surrounding calixarenes. There is one C‒H···N interaction of 3.485(2) Å in which the donor of the weak hydrogen bonding is the carbon atom belonging to the methylene group of the macrocycle and the acceptor is the unprotonated nitrogen atom of Phen X. Finally, there are also C‒H···O interactions of 3.241(2) and 3.294(2) Å between the carbon atoms belonging to the central and unprotonated Phen X rings and sulphonate oxygen atoms of the calixarene. In addition to the


26

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above interactions the Phen X dimer contacts directly with one of the water molecules through the C‒H···O [3.143(2) Å] interaction and the donor in this bond is a carbon atom belonging to the protonated ring of Phen X. Selected interactions present in the structure of complex 5 are listed in the Table S5 (Supporting Information). The 3D cavities occupied by Phen X dimers are defined by four C6S anions shown in Figure 16a and by two hexaaqua magnesium cations. There is one weak C‒H···O interaction [3.174(2) Å] between Phen X and a complexed H2O ligand of hexaaqua magnesium cation (Figure 16b). Oxygen atoms of water molecules coordinated to the magnesium ion are donors of O‒H···O hydrogen bonds [2.776(2), 2.814(2), 2.791(2) and 2.732(2)] Å to sulphonate oxygen atoms of C6S anions. In the crystal of complex 5, the C6S anions do not interact directly with each other. The shortest contact between neighboring calixarenes from the adjacent columns in 5 exists between C7B atoms [C7B⸱⸱⸱C7B 3.462(2) Å] and all other contacts are longer than 4.2 Å. Supramolecular arrangement in the crystal of complex 5 may be regarded as a packing of two types of anionic columns running down the [010] crystallographic axis (Figure 17). One is the described above inclusion polymer of C6S/Phen Y columns and is negatively charged (‒4 charge per unit cell), the second consists of Phen X dimers of and hydrated magnesium ions Mg[H2O]6+ (+4 charge per unit cell) visible in Figure 17a. Water molecules are located in two types of discrete cavities formed between these two types of columns of approximate dimensions 10×8×8 and 12×10×6 Å are created at centers of symmetry 0,0,0 and ½,0,½. (Figure 17b). The walls of these cages are formed by hydrophilic negatively charged sulphonate groups of C6S and rings of Phen ions (both non heterocyclic and heterocyclic protonated and unprotonated parts).


27


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b

Figure 17. Crystal packing of ions and molecules in the structure of complex 5: (a) view along the [010] crystallographic axis; (b) water filled cages, view along the [100] crystallographic axis (molecules of water are omitted for the clarity). Mercury program was used to visualize the solvent accessible channels.45 The total calculated solvent accessible volume in the crystal of complex 5 is 283.55 A3 (11.3%) of the unit cell volume, this space is shown in yellow in Figure 17d. Summary: 3, 4, 5 and TIKVIT structures Three similar 3, 4 and 5 solid state supramolecular assemblies were obtained using parasulphonato-calix[6]arene and 1,10-phenanthroline as the host and guest compounds, respectively. These three new crystal structures show similarities to the previously published TIKVIT entry in CCDC. Even though the crystallization was carried out with mixed solvents, the only solvent molecules present in the crystal were the water molecules located in channels or cages. In all these structures phenanthroline molecules are monoprotonated, i.e. they exist as a monocations, while the host:guest stoichiometry changes from 1:4 in TIKVIT and 5 (due to not fully deprotonated C6S and the presence of an additional cation, respectively) to 1:6 in crystals of 3


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and 4. In all four structures there exist columns of polymerically arranged C6S/Phen 1:2 inclusion complexes. The π‒π interactions play a key role in the formation of these systems. In crystals of 3 and 4 uncomplexed Phen guest cations form tetramers intercalated between the neighboring C6S ions, while in 5 and TIKVIT intercalation of Phen dimers is observed. In all these structures, self-assembly of ions leads to the formation of columns. The spaces between the columns are filled with water molecules and non included Phen ions. Ions and molecules do not form distinct hydrophobic-hydrophilic layers in the crystals. Similar conformation of the host, supramolecular motifs and packing were observed in crystals of parasulphonato-calix[6]arene complexes with quinoline [GIZXUJ] and 8-hydroxyquinoline [GIZYAQ]46, while in the complex of C6S with quaternary ammonium dication of 1,10phenanthroline derivative which is not planar the C6S host adopts the non-symmetric inverted double partial cone conformation and the overall structure presents the honeycomb-type packing TIKVOZ.42 Table 2. Geometry of inclusion compound within the host calixarene. Dihedral angle Phen/reference plane (°)

Depth of inclusion (Å)

H (Å)

68.3(1)

3.859(8)

‒

77.2

4.262

‒

77.6(1) and 76.3(1)

4.26(1) and 4.22(1)

‒

22.6 and 19.5

3.454 and 3.545

11.86

3

26.44(6)

3.44(1)

11.58

4

23.6(1)

3.33(1)

11.22

5

31.75(2)

3.38(6)

12.84

Complex 1 APANUB 2* TIKVIT*


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6**

73.08(3) and 51.13(3)

4.019(6) and 3.459(6)

11.17; 11.37

7**

73.25(3) and 51.85(4)

3.941(6) and 3.528(6)

11.07; 11.22

8**

69.57(2) and 53.69(5)

3.889(3) and 3.501(6)

11.12; 11.53

* Two independent molecules ** Two molecular cavities

Complex 6 Crystals of the complex 6 were obtained from a dichloromethane-ethanol crystallization medium. The asymmetric part of the unit cell (Figure 18) contains one molecule of calix[6]arene C6, 1.5 non-protonated phenanthroline molecules and 0.5 ethanol molecule (Phen X molecule is fully occupied while the Phen Y lies close to the inversion center and was found to be in substitutional disorder with ethanol molecule).

a

b

c

Figure 18. Complex 6: (a) the asymmetric unit; (b) 1:2 inclusion host-guest complex formed by one C6 and two 1,10-phenanthroline molecules; (c) an 1:1:1 inclusion host-guest complex formed by C6, 1,10-phenanthroline and ethanol molecules.


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The C6 molecule adopts the distorted inverted double partial cone conformation stabilized by two pairs of intramolecular O‒H···O hydrogen bonds, each partial cone is stabilized by one pair of bonding [2.648(3), 2.714(2) Å and 2.702(2), 2.770(2) Å, respectively] (Figure 19). Similar conformation of calix[6]arene was observed in the similar complex with piperidinium [VIJLUW]47 but in 6 one cavity is significantly larger than the other. Non-typical inclusion of Phen X with the central aromatic ring located within the cavity increases its diameter by 1.2 Å. Comparison of the conformations of the C6 molecules in complex 6 and VIJLUW is shown in Figure 20.

a

b

Figure 19. The distorted inverted double partial cone conformation of the calix[6]arene in complex 6: (a) top view showing intermolecular O‒H···O hydrogen bonding and cavity diameters; (b) side view.


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b

Figure 20. Superposition of calix[6]arene molecules present in complex 6 (red) and VIJLUW47 (blue): (a) top view; (b) side view. In complex 6 two different inclusion complexes are present: two component one C6/Phen with host:guest stoichiometry 1:2 and three component one C6/Phen/ethanol of stoichiometry 1:1:1 (Figure 18). In both complexes the larger cavity is occupied by Phen X, while in the smaller cavity accommodates either Phen Y or ethanol in the occupancy ratio of 50%. Dihedral angles between the plane of Phen molecules and the reference plane of C6 and the depths of inclusion of Phen X and Y within the partial cones of C6 are given in Table 2. The inclusion of Phen Y molecule inside calixarene cavity is stabilized by bifurcated O‒H···N hydrogen bonding [2.484(3) and 2.933(3) Å] in which the hydroxyl oxygen atom O1F of C6 donates a hydrogen bonds to the nitrogen atoms of Phen Y. Additionally, there are other host-guest interactions such as π‒π with the mean distance of 3.570(6) Å between Phen Y and the A ring of C6, C‒H···π interaction of 3.717(3) Å between the carbon atom placed in the heterocyclic ring of Phen Y and aromatic ring C of C6, and also the C‒H···O interaction of 3.103(5) Å between the carbon atom belonging to the heterocyclic ring of Phen Y guest and hydroxyl oxygen atom O1D of the host. Phen Y molecule also interacts with C6 belonging to the neighboring inclusion complex by two edge to face type π‒π interactions of 3.927(5) and 3.034(5) Å. The ethanol molecule is included


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within the smaller cavity of C6 interchangeably with Phen Y. Solvent inclusion is stabilized by one O‒H···O hydrogen bond [2.685(6) Å] between hydroxyl oxygen of ethanol and the hydroxyl group of ring D of C6, by one C‒H···O interaction of 3.502(6) Å to the hydroxyl oxygen O1B of host and also by one C‒H···π interaction of 3.570(7) Å between carbon atom of solvent and aromatic ring of calixarene. Inclusion of Phen X molecule located within the larger calixarene cavity is stabilized by C‒H···π interaction [3.550(3) Å] between the carbon atom placed in the heterocyclic ring of Phen Y and aromatic ring F of host molecule. Much stronger interaction, namely O‒H···N hydrogen bonding [2.670(2) Å] is present between Phen X molecule and another calixarene in which the hydroxyl oxygen atom O1C of C6 donates a hydrogen bond to the nitrogen atom N1X of Phen X. At the same time C‒H···π interaction [3.566(2) Å] is observed between the carbon atom placed in the heterocyclic ring of Phen X and aromatic ring of yet another calixarene nearby located. Additionally, Phen X molecules form centrosymmetric dimers stabilized by π‒stacking with interplanar distance of 3.536(3) Å. The dimer is trapped within a cavity formed by six C6 molecules (Figure 21). Three more interactions, π‒π type: 3.911(1), 4.508(1) and 4.821(1) Å are present between Phen X dimers and surrounding calix[6]arenes.


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Figure 21. The Phen X dimer trapped between six C6 molecules in complex 6.

Figure 22. Columnar arrangement formed in crystal of complex 6, spacefill model. Described above inclusion complex forms along the [-2-1-3] crystallographic direction columns similar to those observed in 3, 4, 5 and TIKVIT, and also for larger para-sulphonatocalix[8]arene with 1,10-phenanthroline44 (Figure 22). The difference between this columnar arrangement and the previously described ones is that here the columns contain neutral species (contrary to those found in in 3, 4, 5 and TIKVIT) and, due to the non-centrosymmetric nature of the complex and different content of partial cone cavities of C6, the inter-calixarene space is alternately filled with dimers of Phen X molecules and disordered Phen Y/ethanol molecules. The heights of the repeating units (H) in the column are shown in Figure 22 and are summarized in Table 2.


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a

b

c Figure 23. Host-Host interactions in crystal of complex 6: (a) dimer formation via C‒H···O hydrogen bonds; (b) C‒H··· π interactions between adjacent C6 molecules; (c) double layer based on C‒H··· π interactions. Centrosymmetrically related calix[6]arene molecules form dimers via two C‒H···O [3.315(3) Å] hydrogen bonds. The dimers interact by contacts C‒H··· π to form bilayer which are further connected by weak O···O interactions [2.830(2) Å] to form 3D structure (Figure 23).The overall structure of 6 can be considered as a layer-type packing shown in (see Figure Error! Reference source not found.S3 in Supporting Information). One layer consists of inclusion complexes of the C6 with ethanol and Phen being in substitutional disorder, the second layer consists of the dimers of the fully occupied Phen molecules. Complexes 7 and 8 Complexes 7 and 8 are isostructural with complex 6. In complex 7 the acetone molecule replaces the ethanol molecule present in complex 6 while in 8 the THF molecule was found instead of ethanol one. Additionally, in complex 8 the included Phen Y guest is disordered, and is in half substituted by two ethanol molecules giving the whole inclusion pattern even more complicated. Nevertheless, the overall structures and intermolecular interactions are very similar


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to these described in case of complex 6 and are not discussed here in details. Those who are interested, please read the Supporting Information (Tables S7 and S8). For comparison the dihedral angles between the plane of Phen molecules and the reference plane of C6, and the depths of inclusion of Phen X and Y within the partial cones of C6 for both complexes are given in Table 2. CONCLUSION It was shown already that para-sulphonato-calix[4]arene, para-sulphonato-calix[5]arene and para-sulphonato-calix[8]arene as well as para-sulphonato-thiacalix[4]arene and 25,27-Odi(phosphato)-calix[4]arene33 form inclusion complexes with 1,10-phenanthroline. In this paper we show that also 25,27-O-di(carboxymethoxy)-calix[4]arene, para-sulphonato-calix[6]arene and calix[6]arene are capable of interacting with this guest molecule. Eight novel host-guest complexes are reported herein. Complexes 1, 6, 7 and 8 can be classified as molecular inclusion compounds while the 2, 3, 4 and 5 ones are organic salts where the calixarene molecule possessing acidic groups is deprotonated and the basic phenanthroline molecule is protonated. The proton-donor abilities of 25,27-O-di(carboxymethoxy)-calix[4]arene and calix[6]arene towards relatively strong proton-acceptor such as 1,10-phenanthroline is not observed in the studied complexes, nevertheless, doubly deprotonated form of calix[6]arene was observed in its complex with triethylamine [ZERQIW].48 Instead, the unique herring bones like arrangement of the Phen molecules is observed. The inclusion complexes between receptors and substrate are formed mainly through weak π‒π and C‒H···π interactions but a presence of strong hydrogen bonds between host and guest such as O–H···N was also observed (complexes 6, 7 and 8). The six-membered calixarenes show a


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tendency to exist in inverted partial cone conformation and as a consequence the inclusion polymers are formed, even if the substitutional disorder of one of the included molecule is observed. Compared to C4diCA, the C6 and C6S hosts are larger in size and more flexible, and they can act as receptors for several guest molecules simultaneously. Additionally, the C4S and C6S molecules possessing acidic sulphonate groups can be deprotonated and exist in anionic form (the –4 charge for the fully deprotonated C4S and the –6 charge for the fully deprotonated C6S) and, consequently, Coulombic interactions start to play an important role in formation and stabilization of the resulting inclusion compound and the crystal structure. It must be also noted that the deprotonation of the hydroxyl groups, which have weak acidic character, are also possible, like in case of complex 2. The presented results show to some extent an analogy to the phenanthroline intercalation between fragments of the DNA chain and thus confirm the role of calix[n]arenes as useful models of enzymes and biomimetics. On a more speculative front the above results comfort studies on the interactions between anioinic calix[n]arenes and the basic patches found in proteins such as the Histone Nucleosome complex with K/R repeats,49 the DNA binding sequence K/RXK/R found in endonucleases,50 and the glycosylaminoglycan binding sequence K/RXXK/R found in the blood coagulation cascade proteins.51 However the results do not predict binding effects in Serum Albumin binding,52 nor in drug transport across the tight junction CaCo2 cell model of the human gut.53 In order to further advance this study a detailed analysis of the motifs and geometries involved in 1,10-Phenanthroline-anionic calix[n]arene solid state complexes is underway.


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AUTHOR INFORMATION Corresponding Authors * E-mail: [email protected]; *E-mail: [email protected] ACKNOWLEDGMENT This scientific work was partially funded by the Polish Ministry of Science and Higher Education – grant Iuventus Plus 2011 No. 029971 and by the National Science Centre, number of grant decision DEC-2013/11/N/ST5/01920. REFERENCES (1) Gutsche, C. D. Calixarenes: An Introduction: Edition 2. The Royal Society of Chemistry, 2008. (2) Perret, F.; Lazar, A. N.; Coleman A. W. Biochemistry of the para-sulfonatocalix[n]arenes. Chem. Commun., 2006, 23, 2425–2438. (3) Ali, M. K.; Daze, D.; Strongin, D. E.; Rothbart, S. B.; Rincon-Arano, H.; Allen, H. F.. Li, J.; Strahl, B. D.; Hof F.; Kutateladze, T. G. Molecular insights into inhibition of the methylated histone-plant homeodomain complexes by calixarenes. J. Biol. Chem., 2015, 290, 22919–22930. (4) Montasser, I.; Shahgaldian, P.; Perret, F.; Coleman A. W. Solid lipid nanoparticle-based calix[n]arenes

and

calix-resorcinarenes

as

building

blocks:

synthesis,

formulation;

characterization. Int. J. Mol. Sci. 2013, 14, 21899–21942. (5) Danylyuk, O.; Suwinska, K. Solid-state interactions of calixarenes with biorelevant molecules. Chem. Commun., 2009, 5799–5813. (6) W. Steed, J.; Atwood, J. L. Supramolecular Chemistry: Edition 2. John Wiley & Sons, Ltd. 2013.


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(7) Danylyuk, O.; Leśniewska, B.; Suwińska, K.; Matoussi, N.; Coleman, A. W. Structural diversity in the crystalline complexes of para-sulfonato-calix[4]arene with bipyridinium derivatives. Cryst. Growth Des., 2010, 10, 4542–4549. (8) Liao, W.; Liu, C.; Wang, X.; Zhu, G.; Zhao, X.; Zhang, H. 3D metal–organic frameworks incorporating water-soluble tetra-p-sulfonatocalix[4]arene. CrystEngComm, 2009, 11, 2282– 2284. (9) Dalgarno, S. J.; Atwood, J. L.; Raston, C. L. Sulfonatocalixarenes: molecular capsule and ‘Russian doll’ arrays to structures mimicking viral geometry. Chem. Commun., 2006, 44, 4567– 4574. (10) Smith, C. B.; Barbour, L. J.; Makha, M.; Raston, C. L.; Sobolev, A. N. Lanthanideinduced helical arrays of [{Co(III) sepulchrate} ∩ {p-sulfonatocalix[4]arene}] supermolecules. Chem. Commun., 2006, 950–952. (11) Makha, M.; Sobolev, A. N.; Raston, C. L. Constructing 2D porous material based on the assembly of large organic ions: p-sulfonatocalix[8]arene and tetraphenylphosphonium ions. Chem. Commun., 2006, 511–513. (12) Oueslati, I.; Paixaõ, J. A.; Rodrigues, V. H.; Suwińska, K.; Leśniewska, B.; Shkurenko, A.; Eusébio, M. E. S.; Vicens, J.; Maria, T. M. R.; Ramalho, A. L. Generating flexibility in inclusion compounds that possess solvent-accessible voids: an alternative route to control pore size in three-dimensional nanoporous molecular crystals Cryst. Growth Des., 2013, 10, 4512−4517. (13) Gorbatchuk, V. V.; Savelyeva, L. S.; Ziganshin, M. A.; Antipin, I. S.; Sidorov, V. A. Molecular recognition of organic guest vapor by solid adamantylcalix[4]arene. Russ. Chem. Bull., Int. Ed., 2004, 53, 60–65.


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(14) Shkurenko, A.; Seriouna, H.; Kedim, K.; Gervès, J.-B.; Suwińska, K.; Coleman, A. W. Breaking down the interdigitated dimeric structure of calix[4]arene diphosphonic acid: the structures of the complexes with piroxicam and 9-aminoacridine. J. Chem. Crystallogr., 2014, 44, 380–385. (15) Redshaw, C.; Rowe, O.; Hughes, D. L.; Fuller, A-M.; Ibarra, I. A.; Humphrey, S. M. New structural motifs in lithium and zinc calix[4]arene chemistry. Dalton Trans., 2013, 42, 1983–1986. (16) Leśniewska, B.; Perret, F.; Suwińska, K.; Coleman, A. W. Structural characterization of inclusion complexes of para-sulphonato-calix[8]arene with 1,2-bis(4-pyridyl)-ethane and 1,3bis(4-pyridyl)-propane. New ‘double cone’ and ‘up–flat–down’ conformations of parasulphonato-calix[8]arene. CrystEngComm, 2014, 16, 4399−4405. (17) Smirnov, I. V.; Stepanova, E. S.; Ivenskaya, N. M.; Karavan, M. D.; Zaripov, S. R.; Kleshnina, S. R.; Solovieva, S. E.; Antipin, I. S. Cesium and americium extraction from carbonate-alkaline media with O-substituted p-alkylcalix[8]arenes. J. Radioanal. Nucl. Chem., 2017, 314, 1257–1265. (18) Jebors, S.; Leśniewska, B.; Shkurenko, O.; Suwińska, K.; Coleman A. W. Paraacylcalix[6]arenes: their synthesis, per-O-functionalisation, solid-state structures and interfacial assembly properties. J. Incl. Phenom. Macrocycl. Chem., 2010, 68, 207–217. (19) Adarakatti, P. S.; Malingappa, P. Amino-calixarene-modified graphitic carbon as a novel electrochemical interface for simultaneous measurement of lead and cadmium ions at picomolar level. J. Solid State Electrochem., 2016, 20, 3349–3358.


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(20) Suwińska, K.; Leśniewska, B.; Wszelaka-Rylik, M.; Straver, L.; Jebors, S.; Coleman A. W. A dodecameric self-assembled calix[4]arene aggregate with two types of cavities. Chem. Commun., 2011, 47, 8766–8768. (21) Khorasani-Motlagh, M.; Noroozifar, M.; Moodi, A.; Niroomand S. Biochemical investigation of yttrium(III) complex containing 1,10-phenanthroline: DNA binding and antibacterial activity. J. Photochem. Photobiol. B, Biol., 2013, 120, 148–155. (22) Moodi, A.; Khorasani-Motlagh, M.; Noroozifar, M.; Niroomand S. Binding analysis of ytterbium (III) complex containing 1, 10-phenanthroline with DNA and its antimicrobial activity. J. Biomol. Struct. Dyn., 2012, 31, 937–950. (23) Moradi, Z.; Khorasani-Motlagh, M.; Noroozifar M. Synthesis and biological evaluation of a new dysprosium(III) complex containing 2,9-dimethyl 1,10-phenanthroline. J. Biomol. Struct. Dyn., 2016, 35, 300–311. (24) Moradi, Z.; Khorasani-Motlagh, M.; Rezvani, A. R.; Noroozifar M. Evaluation of DNA, BSA binding, and antimicrobial activity of new synthesized neodymium complex containing 29dimethyl 110-phenanthroline. J. Biomol. Struct. Dyn., 2017, 36, 779–794. (25) Momekov, G.; Deligeorgiev, T.; Vasilev, A.; Peneva, K.; Konstantinov, S.; Karaivanova M. Evaluation of the cytotoxic and pro-apoptotic activities of Eu(III) complexes with appended DNA intercalators in a panel of human malignant cell lines. Med. Chem., 2006, 2, 439–445. (26) Leśniewska, B.; Danylyuk, O.; Suwińska, K.; Wojciechowski, T.; Coleman A. W. Supramolecular versatility in the solid-state complexes of para-sulphonatocalix[4]arene with phenanthroline. CrystEngComm, 2011, 13, 3265–3272. (27) Mandolini, L.; Ungaro, R. Calixarenes in Action, Imperial College Press, London, 2000.


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(28) Toutianoush, A.; Schnepf, J.; El Hashani, A.; Tieke, B. Selective ion transport and complexation in layer-by-layer assemblies of p-sulfonato-calix[n]arenes and cationic polyelectrolytes. Adv. Funct. Mater., 2005, 15, 700–708. (29) Rudzevich, Y.; Fischer, K.; Schmidt, M.; Böhmer V. Fourfold tetraurea calix[4]arenes— potential cores for the formation of self-assembled dendrimers. Org. Biomol. Chem., 2005, 21, 3916–3925. (30) Coleman, A. W.; Jebors, S.; Cecillon, S.; Perret F., Garin, D.; Marti-Battle, D.; Moulin M. Toxicity and biodistribution of para-sulfonato-calix[4]arene in mice New J. Chem., 2008, 32, 780–782. (31) Sheldrick, G. M. SHELX-97: Program for Crystal Structure Solution, University of Göttingen, Germany, 1997. (32) Sheldrick, G. M. Crystal structure refinement with SHELXL. Acta Crystallogr. C, 2015, 71, 3–8. (33) Lazar, A. N.; Navaza, A.; Coleman A. W. Solid-state caging of 1,10-phenanthroline π–π stacked dimers by calix[4]arene dihydroxyphosphonic acid. Chem. Commun., 2004, 1052–1053. (34) Wang, K.; Yang, E.-C.; Zhao, X.-J.; Dou, H.-X.; Liu Y. Molecular binding behaviors of sulfonated calixarenes with phenanthroline-diium in aqueous solution and solid state: cavity size governing capsule formation. Cryst. Growth Des. 2014, 14, 4631–4639. (35) Wang, K.; Yang, E.-C.; Zhao, X.-J.; Dou, H.-X.; Liu Y. Molecular binding behaviors of sulfonated calixarenes with phenanthroline-diium in aqueous solution and solid state: cavity size governing capsule formation. Cryst. Growth Des. 2014, 14, 4631–4639.


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(36) Liu, Y.; Chen, K.; Guo, D.-S.; Li, Q.; Song, H.-B. Comparable inclusion and aggregation structures of p-sulfonatothiacalix[4]arene and p-sulfonatocalix[4]arene upon complexation with quinoline guests. Cryst. Growth Des. 2007, 7, 2601–2608. (37) Barboiu, M.; Dumitrescu, D.; Petit, E.; Legrand, Y.-M. van der Lee, A. Crystallizationdriven multicomponent encapsulation of coulombically repulsive guests. Cryst. Growth Des. 2015, 15, 3525–3531. (38) Liu, Y.; Ward, M. D. Molecular Capsules in modular frameworks. Cryst. Growth Des. 2009, 9, 3859–3861. (39) Lazar, A. N., Dupont, N., Navaza, A.; Coleman A. W. Helical aquatubes of calix[4]arene di-methoxycarboxylic acid. Chem. Commun., 2006, 1076–1078. (40) Xie, Z.-Y.; Hou, N.-T.; Zhu, Y.-Z.; Song, H.-B.; Zheng J.-Y. Novel hydrophilic cages based on acetone complex with calix [4] arene dimethoxycarboxylic acid. Chemistry Letters, 2008, 37, 478–479. (41) Dupont, N.; Lazar, A. N.; Perret, F.; Danylyuk, O.; Suwińska, K.; Navaza, A.; Coleman A. W. Solid state structures of the complexes between the antiseptic chlorhexidine and three anionic derivatives of calix[4]arene. CrystEngComm, 2008, 10, 975–977. (42) Liu, Y.; Li, Q.; Guo, D.-S.; Chen K. Polymeric capsules and honeycomb aggregates formed by p-sulfonatocalix[6]arene with phenanthrolinium compounds. Cryst. Growth Des., 2007, 7, 1672–1675. (43) Liu, Y.; Guo, D.-S.; Zhang, H.-Y.; Ma, Y.-H.; Yang E.-C. The structure and thermodynamics of calix[n]arene complexes with dipyridines and phenanthroline in aqueous


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solution studied by microcalorimetry and NMR spectroscopy. J. Phys. Chem. B, 2006, 110, 3428–3434. (44) Leśniewska, B.; Coleman, A. W.; Tauran, Y.; Perret, F.; Suwińska K. Pseudopolymorphs – a variety of self-organization of para-sulphonato-calix[8]arene and phenanthroline in the solid state. CrystEngComm, 2016, 18, 8858–8870. (45) Macrae, C. F.; Bruno, I. J.; Chisholm, J. A.; Edgington, P. R.; McCabe, P.; Pidcock, E.; Rodriguez-Monge, L.; Taylor, R.; van de Streek, J.; Wood P. A. Mercury CSD 2.0 – new features for the visualization and investigation of crystal structures. J. Appl. Cryst., 2008, 41, 466–470. (46) Liu, Y.; Li, Q.; Guo, D.-S.; Chen K. Supramolecular chain-like aggregates and polymeric sandwich complexes constructed from p-sulfonatocalix[4,6]arenes with (8-hydroxy)quinoline guests. CrystEngComm, 2008, 10, 675–680. (47) Lee, Y. J.; Park, K. D.; Yeo, H. M.; Ko, S. W.; Ryu, B. J.; Nam K. C. The molecular recognition of amines with calix[6]arene: conclusive X-ray and NMR evidence for endo and exo complex formation between calix[6]arene and amines. Supramol. Chem., 2007, 19, 167–173. (48) Thuéry, P.; Keller, N.; Lance, M.; Vigner, J-D.; Nierlich M. An inclusion complex between acetonitrile and p-tert-butylcalix[6]arene. J. Incl. Phenom. Mol. Recognit. Chem., 1995, 20, 89–96. (49) Perret, F.; Coleman A. W. Interactions of calix[n]arenes and other organic supramolecular systems with proteins. In Supramolecular Systems in Biomedical Fields; Schneider, H.-J., Ed., RSC, Cambridge, 2013; pp 140–163.


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(50) Tauran, Y.; Anjard, C.; Kim, B.; Rhimi, M.; Coleman A. W. Large negatively charged organic host molecules as inhibitors of endonuclease enzymes. Chem. Commun., 2014, 50, 11404–11406. (51) Da Silva, E.; Ficheux, D.; Coleman A. W. Anti-thrombotic activity of water-soluble calix[n]arenes. J. Incl. Phenom. Macrocycl. Chem., 2005, 52, 201–206. (52) Moubarak, J.; Moreno, E.; Diesis, E.; Coleman A. W. Use of electrospray mass spectromtery to study the interactions between para-sulphonato-calix[4]arene and a series of serum albumin proteins. Chem. J. Moldova, 2009, 4, 94–99. (53) Roka, E.; Vecsernyes, M.; Bacskay, I.; Félix, C.; Rhimi, M.; Coleman, A. W.; Perret F. para-Sulphonato-calix[n]arenes as selective activators for molecule passage across the Caco-2 model intestinal membrane. Chem Commun., 2015, 51, 9374–9376.


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SUPPORTING INFORMATION Table S1. Interactions present in the structure of complex 1. Table S2. Interactions present in the structure of complex 2. Table S3. Interactions present in the structure of complex 3. Table S4. Interactions present in the structure of complex 4. Table S5. Interactions present in the structure of complex 5. Table S6. Interactions present in the structure of complex 6. Table S7. Interactions present in the structure of complex 7. Table S8. Interactions present in the structure of complex 8. Figure S1. Crystal packing of molecules and ions in complex 3, view along the [010] crystallographic axis. Figure S2. Crystal packing of ions and molecules in the crystal of complex 3, view along the [001] crystallographic axis: (a) the stick model; (b) the spacefill model (water molecules are omitted to show small channels). Figure S3. Crystal packing of molecules in the crystal of complex 6: (a) view along the [100] crystallographic direction; (b) view along the [010] crystallographic direction.


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For Table of Contents Use Only

Tuning solid-state calix[n]arene supramolecular assemblies using phenanthroline as the guest molecule Barbara Leśniewska,1* Anthony W. Coleman,2 Florent Perret,3 and Kinga Suwińska 4,5*.

SYNOPSIS Novel X-ray structures of crystalline host-guest complexes (co-crystals and inclusion complexes) formed by phenantroline with unsubstituted calix[6]arene, para-sulphonato-calix[6]arene, para-sulphonato-calix[4]arene and 25,27-Odi(carboxymethoxy)-calix[4]arene are reported.


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Tuning solid-state calix[n]arene supramolecular assemblies using

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