Supra-molecular Chains Research Articles

Helical Supramolecular Polymers Formed via Head-to-Tail Host-Guest Complexation of Chiral Bisporphyrin Monomers with Trinitrofluorenone.

The intermolecular host-guest complexation of head-to-tail monomers consisting of cleft-shaped bisporphyrin and trinitrofluorenone units connected by a chiral binaphthyl linker was employed to construct helically twisted supramolecular polymers. Results from 1H NMR, diffusion-ordered NMR spectroscopy, and viscometry experiments revealed that the supramolecular polymerization of these monomers follows a ring-chain competition mechanism. The introduction of bulky substituents at the linker significantly suppressed the formation of macrocyclic oligomers, whereas smaller alkyl chains facilitated the formation of the cyclic form. The chirally twisted structures of the supramolecular polymers were confirmed using circular dichroism spectroscopy. Atomic force microscopy revealed that the (R)- and (S)-configurations of the binaphthyl linkers induced right- and left-handed helical structures, respectively, in the supramolecular polymer chains. The absence of cooperativity in the supramolecular copolymerization of (R)- and (S)-1a resulted in the formation of stereo-random supramolecular copolymers.

Neutral Terbium(III) Tris(complex) with 4,4,5,5,6,6,6-Heptafluoro-1-(1-methyl-1H-pyrazol-4-yl)hexane-1,3-dione: Synthesis, Structure, and Spectral Luminescence Properties

The reaction of 1,3-diketone containing 1-methyl-1H-pyrazol-4-yl and perfluoropropyl fragments with TbCl3·6H2O in the presence of NaOH in ethanol is studied. The molecular and crystal structures of the complex are studied by single-crystal X-ray diffraction (XRD). Compound [Tb(L)3(EtOH)2] crystallizes in the triclinic crystal system with the space group. The geometry of the coordination polyhedron {LnO8} corresponds to a square antiprism. Intermolecular interactions N…H–O, C–H…O, and C–H…F leading to the formation of supramolecular chains are observed in crystals of the complex. The UV-irradiated complex exhibits green luminescence caused by transitions 5D4 → 7Fj (j = 2–6) characteristic of the Tb3+ ion. The main photophysical luminescence parameters are determined, and the scheme of energy transfer in the complex is proposed. The synthesized compound can be of interest as an independent luminophore or as the initial substance for the synthesis of heteroligand complexes by the substitution of ethanol molecules in the internal coordination sphere.

Synthesis, structural elucidation, and DNA binding behavior of a ternary copper(II) complex featuring substituted bipyridyl and dicarboxylate ligands

The present research study is centered around the synthesis, characterization, and biological application of a ternary mixed-ligand based binuclear Cu(II) complex [Cu2(trans-1,4-chdc)(4,4′-Me2-2,2′-bpy)2(5,5′-Me2-2,2′-bpy)2]·2(cis-H21,4-chdc)·2(BF4¯) (1) by meticulous incorporation of 4,4′-dimethyl-2,2′-bipyridine (4,4′-Me2-2,2′-bpy), 5,5′-dimethyl-2,2′-bipyridine (5,5′-Me2-2,2′-bpy) and cis- andtrans- mixture of 1,4-cyclohexanedicarboxylic acid (H21,4-chdc). Hirshfeld analysis is employed to validate non-bonded interactions, demonstrating the existence of widespread π···π stacking interactions between adjacent 4,4′-Me2-2,2′-bpy ligands at a distance of 3.757 Å, forming a one-dimensional (1D) supramolecular polymer chain. The biological activity of complex 1 is explored via docking study, driven by the inherent biological inclination of the Cu(II) complexes. Agreeably, the coordination complex 1 displays a favorable binding to DNA, specifically binds to the major groove of DNA and the aromatic pyridine ring of the ligand partially intercalates into the base pairs with a binding constant (Kb) of 1.98 × 105 M−1.

4-Amino-3,5-di-chloro-pyridine.

The title compound, C5H4Cl2N2, crystallizes with one mol-ecule in the asymmetric unit. In the crystal, the mol-ecular entities are assembled through strong N-H⋯N hydrogen bonding, forming supra-molecular chains extending along the b-axis direction. These chains are inter-connected by offset π-π stacking inter-actions and consolidated by halogen-π inter-actions. The mol-ecular inter-actions were qu-anti-fied by Hirshfeld surface analysis, showing the significant contributions of Cl⋯H/H⋯Cl (40.1%), H⋯H (15.7%) and N⋯H / H⋯N (13.1%) inter-actions. Energy framework analysis using the CE-B3LYP/6-31 G(d,p) basis set revealed that Coulombic inter-actions make a considerable contribution to the total energy and crystal packing.

Supramolecular Spring‐Like Fe(II) Spin‐Crossover Complexes Experiencing Giant and Anisotropic Thermal Expansion Across Two Distinct Temperature Regimes

AbstractDynamic molecules with tunable chemical and physical properties in response to external stimuli hold great potential for applications in various fields such as information storage, smart molecular machines, and biomimetics. Among them, supramolecular springs and spin‐crossover (SCO) complexes can both undergo visible macroscopic changes under heat or light stimulation. In this study, we synthesized a unique trinuclear Fe(II)‐SCO complex, [(R−L)FeII{Au(CN)2}2] (R 1), using a chiral chelating ligand decorated with rotatable benzyl rings. The [FeAu2] trinuclear molecules form a 21‐helical supramolecular chain via elastic Au Au contacts. Interestingly, the synergy between the multiple dynamic factors (SCO event, rotation of the rings, and flexibility in Au Au distance) endows the complex with multiple switchings in both magnetism and structure, as well as the most intriguing characteristic of giant and anisotropic “breathing” feature in thermal expansion within two distinct temperature regimes. Specifically, complex R 1 undergoes two hysteretic magnetic transitions: a non‐spin transition between 360 and 380 K and an unsymmetric SCO transition in the region of 160–280 K, associated with a symmetry‐breaking event between the non‐polar and polar space groups (P212121↔P21). Both transitions are triggered/accompanied by the rotation (inward vs. outward) of the benzyl rings. Correspondingly, reversible spring‐like motions of the helical chains with the helical pitches varying from 11.345140 K to 12.509280 K then back to 11.630380 K Å are observed in the two distinct temperature regimes. This work demonstrates a significant success in incorporating both SCO and spring‐like motion in one system, paving the way for designing multifunctional dynamic materials for future devices.

Supramolecular Spring-Like Fe(II) Spin-Crossover Complexes Experiencing Giant and Anisotropic Thermal Expansion Across Two Distinct Temperature Regimes.

Dynamic molecules with tunable chemical and physical properties in response to external stimuli hold great potential for applications in various fields such as information storage, smart molecular machines, and biomimetics. Among them, supramolecular springs and spin-crossover (SCO) complexes can both undergo visible macroscopic changes under heat or light stimulation. In this study, we synthesized a unique trinuclear Fe(II)-SCO complex, [(R-L)FeII{Au(CN)2}2] (R 1), using a chiral chelating ligand decorated with rotatable benzyl rings. The [FeAu2] trinuclear molecules form a 21-helical supramolecular chain via elastic Au Au contacts. Interestingly, the synergy between the multiple dynamic factors (SCO event, rotation of the rings, and flexibility in Au Au distance) endows the complex with multiple switchings in both magnetism and structure, as well as the most intriguing characteristic of giant and anisotropic "breathing" feature in thermal expansion within two distinct temperature regimes. Specifically, complex R 1 undergoes two hysteretic magnetic transitions: a non-spin transition between 360 and 380 K and an unsymmetric SCO transition in the region of 160-280 K, associated with a symmetry-breaking event between the non-polar and polar space groups (P212121↔P21). Both transitions are triggered/accompanied by the rotation (inward vs. outward) of the benzyl rings. Correspondingly, reversible spring-like motions of the helical chains with the helical pitches varying from 11.345140 K to 12.509280 K then back to 11.630380 K Å are observed in the two distinct temperature regimes. This work demonstrates a significant success in incorporating both SCO and spring-like motion in one system, paving the way for designing multifunctional dynamic materials for future devices.

Controlled Helical Organization in Supramolecular Polymers of Pseudo-Macrocyclic Tetrakisporphyrins.

Tetrakisporphyrin monomers with amino acid side chains at each end form intramolecular antiparallel hydrogen-bonds to adopt chirally twisted pseudo-macrocyclic structures that result in right-handed and left-handed (P)- and (M)-conformations. The pseudo-macrocyclic tetrakisporphyrin monomers self-assembled to form supramolecular helical pseudo-polycatenane polymers via head-to-head complementary dimerization of the bisporphyrin cleft units in an isodesmic manner. The formation of one-handed supramolecular helical pseudo-polycatenane polymers was confirmed by circular dichroism (CD) spectroscopy. The methyl and iso-propyl groups at the stereogenic center greatly enhanced the induced circular dichroism in the Soret bands of the supramolecular helical pseudo-polycatenane polymers. The induced CDs were reduced upon the introduction of large iso-butyl and tert-butyl groups. Atomic force microscopy revealed well-grown and long supramolecular helical pseudo-polycatenane polymer chains with chain lengths in the range of 361 to 13.6 nm. The right-handed helical chains were established by the self-assembly of the right-handed (P)-conformation of the pseudo-macrocyclic monomer.

Self-assembly of tetra nuclear lanthanide (Pr, Nd) hydroxo clusters with functionalized β-diketone: Experimental and theoretical studies

Reaction of LnCl3·6H2O (Ln = Pr, Nd) with functionalized β-Diketone {ortho-hydroxydibenzoylmethane (HO-DBM)} in 1:2 ratio in methanol and in presence of triethylamine (excess) as base yielded two tetra nuclear lanthanide hydroxo clusters of composition [Ln4(O-DBM)4(HO-DBM)4(µ3-OH)2][Et3NH]2.3CH2Cl2, (Ln = Pr (1), Nd (2)). The clusters 1 and 2 has been structurally characterized by single crystal X-ray diffraction. A one-dimensional supramolecular chain is observed in the solid state structure (2), where dichloromethane solvent molecules are linked to the phenyl rings of adjacent diketone linkers through CH⋯π and Cl⋯π interactions. Theoretical studies support the stability of structure (2), with calculated geometric parameters aligning with experimental findings.

Exploring supramolecular C-Br…Br-C interactions as organizing tools in a novel Ni(II)-tetrabromophthalate complex. Crystal structure and solvatochromism studies

The understanding of the non-covalent halogen…halogen interaction inside coordination complexes has special interest as design tools in crystal engineering and coordination chemistry. In this work, we show the use of the supramolecular C-Br…Br-C interactions as a tool in the crystalline organization of a Ni(II) complex and its solvatochromic properties. To do so, we selected the 3,4,5,6-tetrabromophthalate (TBrPh) ligand where the Br atoms pointing outside to favor their self-assembly through these interactions.Thus, a novel complex, [Ni(tmeda)(TBrPh)(H2O)3]•CH3OH was synthesized by the reaction between [Ni(tmeda)].(NO3)2 (tmeda = N, N, N’, N’-tetramethylethylenediamine) and K2TBrPh. The Ni(II)-complex was structurally analyzed by single-crystal X-ray diffraction, Hirshfeld surfaces, multiple analytical tools and DFT calculations.Structural analysis shows that Ni(II)-complex has 1D supramolecular chains based on the cooperativity of intra/inter-molecular charged-assisted hydrogen bonds of type Ni-OH2…O and Csp2-Br…Br-Csp2 interactions into 2D networks. These Br…Br interactions organize the crystal packing in the solid state as is evidenced by the molecular electrostatic potential studies and Plot of Hirsfeld surface.This Ni(II)-complex displays solvatochromism with a wide range of solvents (alcohols, DMF, CH3CN, chlorinated solvents), and solvent-dependent absorption maxima presents linear behavior as a function of their dielectric constant.

Regioselective and Homochiral Supramolecular Polymerization of Nanotadpole Aggremers of Poly(phenylacetylene) Derivatives.

Biological homochirality is a signature of life. Supramolecular polymerization is effective to achieve high hierarchical homochirality in nature, but has not been well-explored. Herein, we report regioselective and homochiral supramolecular polymerization of chiral nanotadpole aggregates made of either synthetic helical poly(phenylacetylene)s or chirality-amplified co-assembly of chiral and achiral poly(phenylacetylene)s. The twisted nanotadpole aggregates with high screw-sense preference polymerized as monomers (aggremers) into supramolecular chains in a head-to-tail regioselective and stepwise manner. Supramolecular copolymerization of enantiomeric aggremers favored formation of homochiral hierarchical supramolecular structures as visualized by TEM. Chiral hexagonal columnar mesophase of aggremers was responsive for the stereoselectivity. The work opens a gate to controllably and effectively construct functional chiral supramolecular materials and deepens the understanding of hierarchical biological homochirality.

Regioselective and Homochiral Supramolecular Polymerization of Nanotadpole Aggremers of Poly(phenylacetylene) Derivatives

Biological homochirality is a signature of life. Supramolecular polymerization is effective to achieve high hierarchical homochirality in nature, but has not been well‐explored. Herein, we report regioselective and homochiral supramolecular polymerization of chiral nanotadpole aggregates made of either synthetic helical poly(phenylacetylene)s or chirality‐amplified co‐assembly of chiral and achiral poly(phenylacetylene)s. The twisted nanotadpole aggregates with high screw‐sense preference polymerized as monomers (aggremers) into supramolecular chains in a head‐to‐tail regioselective and stepwise manner. Supramolecular copolymerization of enantiomeric aggremers favored formation of homochiral hierarchical supramolecular structures as visualized by TEM. Chiral hexagonal columnar mesophase of aggremers was responsive for the stereoselectivity. The work opens a gate to controllably and effectively construct functional chiral supramolecular materials and deepens the understanding of hierarchical biological homochirality.

Supramolecular Spin Chains via Radical-Radical Contacts Stabilizing Ferromagnetic Interactions Between Heisenberg or Ising-Like Spins.

A new paramagnetic ligand, 4-(2'-4-(2''-furyl)-pyrimidyl)-1,2,3,5-dithiadiazolyl (furylpymDTDA) and three transition metal coordination complexes, M(hfac)2(furylpymDTDA) M=Mn, Co, Ni; hfac=1,1,1,5,5,5-hexafluoroacetylacetonato-), are reported. The solid-state structures are influenced by the geometry of the coordination sphere of the M(II) centers: trigonal (Mn) vs. octahedral (Co and Ni). While the hs-Mn(II) complex exhibits pairwise multi-centre 2-electron bonds (i. e., pancake bonds) between the planar π radical DTDA moieties, the hs-Co(II) and Ni(II) complexes crystallize with close contacts between coordinated furylpymDTDA radical ligands that define linear 1D arrays of molecular units. The magnetic data for the hs-Co(II) and Ni(II) complexes indicate ferromagnetic (FM) interactions between molecular units, apparently mediated by radical-radical contacts along the supramolecular chains. Computational analysis suggests proximity between regions of large α- and β-spin density on neighbouring molecular sites enabling FM exchange, in accordance with the McConnell I mechanism. The magnetic data for the Ni(II) complex are consistent with a Heisenberg spin chain, whereas the hs-Co(II) complex exhibits Ising-like spin chain behaviour and a magnetic phase transition to an FM ordered state at 4.6 K.

Novel synthesis of 1,6- and 1,4-dialkyl glycolurils and their supramolecular organization

New regioselective reaction of 1-alkyl-5-hydroxy-4,5-diphenyl-1H-imidazol-2(5H)-one with alkylureas gives predominantly 1,6-dialkyl-3a,6a-diphenylglycolurils along with minor quantities of the 1,4-isomers. In case of propyl homologues, co-crystal of 1,6/1,4-dipropyl glycolurils would precipitate. Based on the analysis of the crystal packing of the products, new type of supramolecular chains for 1,4-disubstituted glycolurils has been identified.

Formation and Dynamics of Imidazole Supramolecular Chains Investigated by Deep Potential Molecular Dynamics Simulation.

Imidazole-based materials have attracted considerable attention due to their promising potential for facilitating anhydrous proton transport at high temperatures. Herein, a machine learning-based deep potential (DP) model for bulk imidazole with first-principles accuracy is developed. The trained model exhibits remarkable accuracy in predicting energies and forces, with minor errors of 4.71 × 10-4 eV/atom and 3.23 × 10-2 eV/Å, respectively. Utilizing DP molecular dynamics simulations, we have systematically investigated the temperature-dependent formation and dynamics of imidazole supramolecular chains through the partial radial distribution function, quantification of hydrogen bond numbers, incoherent intermediate scattering function, and diffusion coefficient. The findings reveal the influence of temperature on the proton transport path following either the "Grotthuss" and "vehicle" mechanism.

(Z)-N-(2,6-Di-methyl-phen-yl)-1-[(2-meth-oxy-phen-yl)amino]-methanimine oxide methanol monosolvate.

In the title solvate, C16H18N2O2·CH4O, the dihedral angles between the formamidine backbone and the pendant 2-meth-oxy-phenyl and 2,6-di-methyl-phenyl groups are 14.84 (11) and 81.61 (12)°, respectively. In the crystal, the components are linked by C-H⋯O, O-H⋯O and C-H⋯ π hydrogen bonds, generating a supra-molecular chain that extends along the crystallographic a-axis direction.

Highly Water‐Dispersible Spiropyran‐Octapeptide Supramolecules: Efficient, Multi‐processable, and Versatile Photoswitches for Time‐Dependent Dual‐Mode Encryption

AbstractWith exceptional photochromic and photoluminescent properties, spiropyrans have demonstrated significant potential for advanced information encryption and anti‐counterfeiting applications. However, its inherent water insolubility leads to incompatibility with aqueous polymers, and even more, its ease of leaching from the matrix hinders the formation of stable stimuli‐responsive platforms through direct blending with all polymers. Here, the fabrication of amphiphilic spiropyran‐octapeptide molecules is reported that can spontaneously self‐assemble into highly water‐dispersible supramolecular nanofibers in water. These assemblies exhibit universal polymer matrix compatibility while retaining the rapid photo‐responsiveness of spiropyrans. The formation of strong interactions between the supramolecular assembly and polymer chains ensures the long‐term stability of the resultant stimuli‐responsive materials in aqueous environments. These platforms fully preserve the base polymers’ processing properties, with silk fibroin as the matrix offering exceptional opportunities for constructing photo‐responsive platforms in various forms (e.g., films, gels, fibers, and coatings) with multiple functionalities using diverse solution processing techniques. Integrating distinct photochromic and photoluminescent responses within a single format without interference, combined with environmental stability and processing flexibility, enables the creation of dual‐mode, high‐security encryption devices for diverse application scenarios. The outlined strategy provides innovative concepts for developing high‐performance, versatile intelligent systems utilizing stimulus‐responsive molecules.

Crystal structures and properties of derivatives of the alkaloid matrine: salts and hydrate forms.

We report the crystal structures of three matrine derivatives, namely, the salts (1R,2R,9S,17S)-6-oxo-7,13-diazatetracyclo[7.7.1.02,7.013,17]heptadecan-13-ium (2E)-3-(3,4-dihydroxyphenyl)prop-2-enoate (matrine caffeinate) sesquihydrate, C15H25N2O+·C9H7O4-·1.5H2O (Matrine-CA), and the 2-hydroxybenzoate (salicylate) monohydrate, C15H25N2O+·C7H5O3-·H2O (Matrine-SA), as well as the 1.75-hydrate form, (1R,2R,9S,17S)-7,13-diazatetracyclo[7.7.1.02,7.013,17]heptadecan-6-one 1.75-hydrate, C15H24N2O·1.75H2O (Matrine-H). Each derivative exhibited a consistent molecular conformation for the matrine core, which is notably distinct from that of the anhydrous form. Notably, both salts crystallized in the orthorhombic space group P212121, with an asymmetric unit featuring one cation and one anion. Within the two salt structures, intermolecular proton transfer between matrine and the acid is observed, culminating in the formation of a matrine cation protonated at the tertiary amine N site. The Matrine-CA crystal packing is manifested as a three-dimensional (3D) network arising from one-dimensional (1D) supramolecular helical chains, stabilized by N-H...O and O-H...O hydrogen bonds. In the case of Matrine-SA, the matrine cation is interconnected via hydrogen bonds with salicylate anions and water molecules, also forming a 1D helical motif. The structure of the hydrate form, Matrine-H, is reported again with the disordered solvent molecules accurately located. To further elucidate the structural attributes, Hirshfeld surface analysis and fingerprint plots are employed, offering a nuanced perspective on the intermolecular contacts and interactions within these crystalline forms.

Synthesis, crystal structure and Hirshfeld surface analysis of a new copper(II) complex based on diethyl 2,2'-(4H-1,2,4-triazole-3,5-di-yl)di-acetate.

The title compound, bis-[μ-2,2'-(4H-1,2,4-triazole-3,5-di-yl)di-acetato]-bis-[di-aqua-copper(II)] dihydrate, [Cu2(C6H5N3O4)2(H2O)4]·2H2O, is a dinuclear octa-hedral CuII triazole-based complex. The central copper atoms are hexa-coordinated by two nitro-gen atoms in the equatorial positions, two equatorial oxygen atoms of two carboxyl-ate substituents in position 3 and 5 of the 1,2,4-triazole ring, and two axial oxygen atoms of two water mol-ecules. Two additional solvent water mol-ecules are linked to the title mol-ecule by O-H⋯N and O⋯H-O hydrogen bonds. The crystal structure is built up from the parallel packing of discrete supra-molecular chains running along the a-axis direction. Hirshfeld surface analysis suggests that the most important contributions to the surface contacts are from H⋯O/O⋯H (53.5%), H⋯H (28.1%), O⋯O (6.3%) and H⋯C/C⋯H (6.2%) inter-actions. The crystal studied was twinned by a twofold rotation around [100].

Recurrent Supramolecular Patterns in a Series of Salts of Heterocyclic Polyamines and Heterocyclic Dicarboxylic Acids: Synthesis, Single-Crystal X-ray Structure, Hirshfeld Surface Analysis, Energy Framework, and Quantum Chemical Calculations

A series of novel salts based on aromatic polyamines and 2,3-pyrazinedicarboxylic acid, such as C10H12N6O5 (1), C10H9ClN6O4 (2), C11H10N8O4 (3), and C14H17N16O5.5 (4) or 3,4-thiophenedicarboxylic acid, such as C10H10N4O4S (5), C10H9ClN4O4S (6), and C10H10N4O4S2 (7), were synthesized and characterized by single-crystal X-ray diffraction. All compounds crystallize in a monoclinic space group. The structure was subjected to complex Hirshfeld surface analysis, molecular electrostatic potential, enrichment ratio, and energy framework calculations. The influence of different cations on the packing of 3-carboxypyrazine-2-carboxylate and 4-carboxythiophene-3-carboxylate anions in the crystal lattice was studied. O…H/H…O interactions are the main contributor in all crystals. In addition, in a series of pyrazine-containing structures, N(C)…H/H…N(C) interactions have relevance, while in a series of thiophene-based compounds, C…H/H…C and S…H(O)/H(O)…S. In addition, Cl-based interactions are observed in compound 2. According to the enrichment ratio calculations, O…H/H…O and C…C are the most preferable interactions in all structures. The energy frameworks are dominated by the dispersive contribution, only in compound 3 is the electrostatic term dominant. The analyzed structures reveal intra- and intermolecular recurrent supramolecular synthons. In both series of crystals, the robust H-bonded centrosymmetric dimer R22(8) as homo- or as heterosynthon (in compounds 2, 3, 6, and 7) and the intramolecular synthon S(7) generated by O-H…O interactions (in compounds 2, 6, and 7) are present. The supramolecular patterns formed by π…π (C…C) and C-O(Cl,S)…C are also noticeable. Notably, a dual synthon linking the supramolecular chain via π…π interactions and the homosynthon R22(8) via N-H…N interactions is visible in both series of new salts. A library of H-bonding motifs at diverse levels of supramolecular architecture is provided. We extended the analysis of intramolecular H-bonding motifs to similar structures deposited in the Cambridge Structural Database. Another important feature is the existence of an intramolecular O…H…O bridge between two neighboring carboxylic groups as substituents in anions in compounds 3 and 5. In this context, we performed quantum theory of atoms-in-molecule calculations to reveal more details.

Neutral guest binding by meso‑3,5-bis(trifluoromethyl)phenyl two-wall calix[4]pyrrole: N-oxide recognition features and unique acetonitrile binding mode

Two-wall calix[4]pyrroles bearing two aryl substituents at diametrically opposed meso-positions have been well explored toward the recognition and sensing of anionic substrates. However, their ability to form stable complexes with neutral guests remains underexplored. Herein, we report the heterocyclic N-oxides (such as pyridine N-oxide (PNO), 4-methylpyridine N-oxide (MPNO), and 4-phenylpyridine N-oxide (PPNO)) binding features of meso-3,5-bis(trifluoromethyl)phenyl two-wall calix[4]pyrrole 1. Single crystal X-ray diffraction analysis of the PNO complex of 1 revealed the formation of two types of closely resembled 1/1 complexes within the same crystal, wherein the calix[4]pyrrole core adopted a cone-like conformation and the PNO was bound to the cleft delineated by two aromatic walls adopting pseudo-edge-to-face (PETF) geometry. MPNO formed only one type of 1/1 complex with receptor 1 having PETF geometry in the solid state. Solution phase interaction of 1 with PNO, MPNO, and PPNO was investigated by 1H NMR spectroscopic titrations carried out in CD3CN. On the other hand, X-ray diffraction analysis of single crystals of 1, grown from CH3CN solution, unveiled the formation of a 1/2 host-acetonitrile solvate containing an unstable arrangement of CH3CN dimer displaying a unique CH3CN coordination mode in the solid state. Furthermore, a unique 1D supramolecular chain of CH3CN was stabilized within the narrow channel in the crystal lattice of 1•(CH3CN)2.