Molecular mechanical and quantum chemical study of the species involved in the hydrolysis ofcis-diamminedichloroplatinum(II) and substitutedbis(ethylenediamine)-dichloroplatinum(II) complexes II. Simulated transition states

Summary cis-Diamminedichloroplatinum(II) (cisplatin) and its substituted ethylenediamine derivativescis-PtCl₂(R ₂ en) (en=ethylenediamine,R=H,Ph,2-,3-, and 4-PhOH) have been investigated with respect to the possible structures of the hypothetical Transition State Complexes (TSC) of the hydrolytic S_N2 reaction in which one Cl is replaced by H₂O.TSCs withtrigonal bipyramid (TBP) andsquare pyramid (SP) geometry (coordination number 5), have been studied by Molecular Mechanics (MM) and ExtendedHückel (EH) methods. TheEH andMM energies as well as the number of occurrence (entropy factor) for the cisplatinum compound point to a preferredTBP TSC geometry with NH₃ and Cl in axial positions. However, foren and substituteden compounds,TSCs withSP geometries (Cl in apical position) are preferred. The calculatedEH andMM energies of theTBP andSP structures do not differ significantly andTBP SP interconversions may play an essential role inTSC formation. To improve the discrimination, theMM-optimized geometries were treated in terms of displacement coordinates for D_3h (TBP) and C_4v (SP) by calculating the total distortion vectors (DV).DV identified once again theTBP with NH₃ and Cl in axial position as the least-distorted conformer, but it also revealed the combinations of displacement coordinates which shape theTSC geometry.

---

Molekularmechanische und quantenchemische Untersuchung der bei der Hydrolyse voncis-Diammindichlorplatin(II) und substituiertenBis(ethylendiamin)dichlorplatin(II)-Komplexen auftretenden Spezies, 2. Mitt. Simulierte Übergangszustände

Zusammenfassung cis-Diammindichlorplatin(II) (Cisplatin) und seine substituierten Ethylendiaminderivatecis-PtCl₂(R ₂ en) (en=Ethylendiamin,R=H, Ph, 2-, 3- und 4-PhOH) wurden im Hinblick auf mögliche Strukturen der hypothetischen Übergangszustandkomplexe (TSC) der hydrolytische S_N2-Reaktion (Substitution eines Cl-Atoms durch H₂O) untersucht.TSCs mit trigonalbipyramidalen (TBP) und quadratisch-pyramidalen (SP) Geometrien (Koordinationszahl 5) wurden mit molekularmechanischen (MM) und Extended-Hückel-Methoden (EH) behandelt.EH- undMM-Energien sowie entropische Faktoren weisen für Cisplatin auf eine trigonale Bipyramide mit NH₃ und Cl in axialen Positionen als bevorzugteTSC-Geometrie hin, während für Komplexe miten-LigandenSP-Geometrien mit Cl in der apicalen Position energetisch begünstigt sind. Da die berechnetenEH- undMM- Energien fürTBP- undSP-Geometrien sehr ähnlich sind, spielen möglicherweiseTBP-SP-Umwandlungen eine wesentliche Rolle bei der Bildung derTSCs. Zur Verbesserung der Unterscheidung wurden für dieMM-optimierten Geometrien die Verschiebungsvektoren (DV) bezüglich D_3h (TBP) und C_4v (SP) berechnet. Daraus resultierte erneut die trigonale Bipyramide mit NH₃ und Cl in den axialen Positionen als das am wenigsten gespannte Konformere; des weiteren konnten mit dieser Methode die Kombinationen der Verschiebungskoordinaten erhalten werden, die für die Ausbildung derTSC-Geometrie verantwortlich sind.

     

Nature and importance of three-body interactions in the (H2O)2HCl trimer

 The nature and importance of nonadditive three-body interactions in the (H₂O)₂HCl cluster have been studied by the supermolecule coupled-cluster method and by symmetry-adapted perturbation theory (SAPT). The convergence of the SAPT expansion was tested by comparison with the results obtained from the supermolecule coupled-cluster calculations including single, double, and noniterative triple excitations [CCSD(T)]. It is shown that the SAPT results reproduce the converged CCSD(T) results within 3% at worst. The SAPT method has been used to analyze the three-body interactions for various geometries of the (H₂O)₂HCl cluster. It is shown that the induction nonadditivity is dominant, but it is partly quenched by the first-order Heitler–London-type exchange and higher-order exchange–induction/deformation terms. This implies that the classical induction term alone is not a reliable approximation to the nonadditive energy and that it will be difficult to approximate the three-body potential for (H₂O)₂HCl by a simple analytical expression. The three-body energy represents as much as 21–27% of the pair CCSD(T) intermolecular energy. Received: 15 September 1999 / Accepted: 3 February 2000 / Published online: 2 May 2000     

Hydrogen sulphide H2S and noble gases (Ng = He,Ne, Ar,Kr, Xe,Rn) complexes: A theoretical study of their dynamics,spectroscopy, and interactions

In this work, some basic features of the intermolecular bond in gas phase H₂S-Ng complexes (Ng = He, Ne, Ar, Kr, Xe, and Rn) have been investigated in detail, coupling information from scattering experiments with results of quantum chemical calculations at the CCSD(T)/aug-cc-pVTZ level. Spectroscopic constants, rotovibrational energies, and lifetime as a function of temperature have been evaluated for the complete family of H₂S-Ng systems, and an extensive study of involved intermolecular interactions has been performed. In particular, their nature has been characterized by exploiting Atoms-In-Molecules (AIM), Non-Covalent Interactions (NCI), Symmetry-Adapted Perturbation Theory (SAPT), and Charge Displacement (CD) methods, and it was found that all complexes are bound essentially by near-isotropic van der Waals forces, perturbed by weak-stabilizing charge (electron) transfer contributions. Obtained results also show that these additional contributions increase from He up to Rn, providing an appreciable chemical-stabilizing effect of the noncovalent intermolecular bond for H₂S-heavier Ng systems.     

Solubility,volumetric properties and viscosity of the sustainable systems of liquid poly(ethylene glycol) 200 with imidazolium- and phosphonium-based ionic liquids: Cation and anion effects

In this work, solubility, volumetric and viscosity behavior were studied for the systems containing the environmentally acceptable compounds: liquid poly(ethylene glycol) (PEG200) and three ionic liquids: 1-butyl-3-methylimidazolium dicyanamide ([C₄mim][dca]), trihexyltetradecyl phosphonium dicyanamide ([P_6,6,6,14][dca]) and 1-hexyl-3-methylimidazolium bis{(trifluoromethyl)sulfonyl}amide ([C₆mim][NTf₂]). The studies were performed in a temperature range (288.15 to 328.15) K and at a pressure of 0.1 MPa. For the only system that evidenced limited miscibility, namely (PEG200 + [P_6,6,6,14][dca]), the temperature-composition phase diagram at 0.1 MPa was determined, mapping the existing one- and two-phase regions. In the homogeneous region of this diagram, densities and viscosities were measured and the excess molar volumes, as well as deviations in viscosity were calculated. For the other two systems, as they are always homogeneous in the temperature ranges of the present work, these measurements and calculations were performed in the full range of compositions. The molecular interactions in the studied systems were scrutinized using the obtained excess molar volumes, deviations of viscosity, as well as Kamlet–Taft parameters of PEG200 and the ionic liquids. In addition, the excess molar Gibbs free energies of activation of viscous flow and the related enthalpies and entropies were calculated and introduced to take into consideration the differences in size of the molecules.     

A Cobalt(I) Pincer Complex with an η2‐Caryl−H Agostic Bond: Facile C−H Bond Cleavage through Deprotonation,Radical Abstraction,and Oxidative Addition

The synthesis and reactivity of a Co^I pincer complex [Co(?³P,CH,P‐P(CH)P^NMe‐iPr)(CO)₂]⁺ featuring an η²‐ C_aryl?H agostic bond is described. This complex was obtained by protonation of the Co^I complex [Co(PCP^NMe‐iPr)(CO)₂]. The Co^III hydride complex [Co(PCP^NMe‐iPr)(CNtBu)₂(H)]⁺ was obtained upon protonation of [Co(PCP^NMe‐iPr)(CNtBu)₂]. Three ways to cleave the agostic C?H bond are presented. First, owing to the acidity of the agostic proton, treatment with pyridine results in facile deprotonation (C?H bond cleavage) and reformation of [Co(PCP^NMe‐iPr)(CO)₂]. Second, C?H bond cleavage is achieved upon exposure of [Co(?³P,CH,P‐P(CH)P^NMe‐iPr)(CO)₂]⁺ to oxygen or TEMPO to yield the paramagnetic Co^II PCP complex [Co(PCP^NMe‐iPr)(CO)₂]⁺. Finally, replacement of one CO ligand in [Co(?³P,CH,P‐P(CH)P^NMe‐iPr)(CO)₂]⁺ by CNtBu promotes the rapid oxidative addition of the agostic η²‐C_aryl?H bond to give two isomeric hydride complexes of the type [Co(PCP^NMe‐iPr)(CNtBu)(CO)(H)]⁺.     

Ring-polymer Molecular Dynamics Simulation for the Adsorption of H2 on Ice Clusters (H2O)n (n=8, 10, and 12)

In the interstellar medium, the H₂ adsorption and desorption on the solid water ice are crucial for chemical and physical processes. We have recently investigated the probabilities of H₂ sticking on the (H₂O)₈ ice, which has quadrilateral surfaces. We have extended the previous work using classical MD and ring-polymer molecular dynamics (RPMD) simulations to the larger ice clusters, (H₂O)₁₀ and (H₂O)₁₂, which have pentagonal and hexagonal surfaces, respectively. The H₂ sticking probabilities decreased as the temperature increased for both cluster cases, whereas the cluster-size-independent profiles were observed. It is thought that the size independence of the probabilities is qualitatively understood from the similar binding energies for all the three cluster systems. Furthermore, the RPMD sticking probabilities are smaller than the classical ones because of the reduction in the binding energies owing to nuclear quantum effects, such as vibrational quantization.     

Organometallic polymers assembled from cation-pi interactions: use of ferrocene as a ditopic linker within the homologous series [{(Me3Si)2NM}2.(Cp2Fe)]infinity (M=Na, K, Rb, Cs; Cp=cyclopentadienyl)

Addition of ferrocene to solutions of alkali metal hexamethyldisilazides M(HMDS) in arenes (in which M=Na, K, Rb, Cs) allows the subsequent crystallization of the homologous series of compounds [{(Me(3)Si)(2)NM}(2) (Cp(2)Fe)](infinity) (1-4). Similar reactions using LiHMDS led to the recrystallization of the starting materials. The crystal structures of 1-4 reveal the formation of one-dimensional chains composed of dimeric [{M(HMDS)}(2)] aggregates, which are bridged through neutral ferrocene molecules by eta(5)-cation-pi interactions. In addition, compounds 3 and 4 also contain interchain agostic M--C interactions, producing two-dimensional 4(4)-nets. Whereas 1 and 2 were prepared from toluene, the syntheses of 3 and 4 required the use of tert-butylbenzene as the reaction media. The attempted crystallization of 3 and 4 from toluene resulted in formation of the mixed toluene/ferrocene solvated complexes [{(Me(3)Si)(2)NM)(2)}(2) (Cp(2)Fe)(x)(Tol)(y)](infinity) (in which M=Rb, x=0.6, y=0.8, 5; M=Cs, x=0.5, y=1, 6). The extended solid-state structures of 5 and 6 are closely related to the 4(4)-sheets 3 and 4, but are now assembled from a combination of cation-pi, agostic, and pi-pi interactions. The charge-separated complex [K{(C(6)H(6))(2)Cr}(1.5)(Mes)][Mg(HMDS)(3)] (15) was also structurally characterized and found to adopt an anionic two-dimensional 6(3)-network through doubly eta(3)-coordinated bis(benzene)chromium molecules. DFT calculations at the B3 LYP/6-31G* level of theory indicate that the binding energies of both ferrocene and toluene to the M(HMDS) dimers increases in the sequence Li相似文献   

Trapping phosphate anions inside the [Ag4I] framework: Structure, bonding, and properties of Ag4I(PO4)

Orange-red Ag₄I(PO₄) crystallizes in the monoclinic system, space group P2₁/m (No. 11), with the unit cell dimensions a=9.0874(6) Å, b=6.8809(5) Å, c=11.1260(7) Å, β=109.450(1)°, and Z=4. The crystal structure is fully ordered; it comprises the silver-iodine three-dimensional positively charged framework hosting the tetrahedral PO₄³⁻ guest anions. The framework features high coordination numbers for iodine and manifold Ag-Ag bonds ranging from 3.01 to 3.46 Å. The Ag-Ag interaction is bonding, it involves silver 4d and 5s orbitals lying, together with the orbitals of iodine, just below the Fermi level. Though the orbitals of silver and iodine define the conducting properties of the title compound, the interaction between the framework and the guest anions is also important and is responsive to the number of the silver atoms surrounding the PO₄³⁻ tetrahedra. Ag₄I(PO₄) melts incongruently at 591 K and produces a mixture of the silver phosphate and an amorphous phase upon cooling. Pure Ag₄I(PO₄) is a poor conductor with a room temperature conductivity of 3×10⁻⁶ S m⁻¹. The discrepancies between the properties observed here and those reported previously in the literature are discussed.     

New Organophosphorus Proligands and Amide Precursors: Crystal and Molecular Structures of Ph2P(X)NH(C6H3Pri 2-2,6) (X = O,S) and (OPPh2)(O2SMe)N(C6H3Pri 2-2,6)

The new organophosphorus proligand (OPPh₂)(O₂SMe)NR (R = C₆H₃Prⁱ ₂–2,6) (3) was prepared as a white crystalline solid by reacting the lithiated compound Li[Ph₂P(O)NR] with MeSO₂Cl in a 1:1 molar ratio. The precursor Ph₂P(O)NHR (1), as well as its thio analogue Ph₂P(S)NHR (2), were obtained in the reaction between the lithiated amine RNHLi and the corresponding organophosphorus chloride. All compounds were characterized by multinuclear (¹H, ¹³C, and ³¹P) NMR spectroscopy. The molecular structures of 1–3 were established by single-crystal X-ray diffraction. A zigzag polymeric chain is formed in the crystals of 1 and 2 by hydrogen N–H···X (X = O, S) bonding, while the crystal of 3 contains discrete monomeric units with a syn–syn conformation of the O?P(C)₂–N–S(C)(?O)₂ skeleton.

Supplemental materials are available for this article. Go to the publisher's online edition of Phosphorus, Sulfur, and Silicon and the Related Elements to view the free supplemental file.     

Albidosides H and I,two new triterpene saponins from the barks of Acacia albida Del. (Mimosaceae)

Two new triterpene saponins, albidosides H (1) and I (2), along with the three known saponins were isolated from the barks of Acacia albida. Their structures were elucidated on the basis of extensive 1D- and 2D-NMR studies and mass spectrometry. Albidosides H (1) and I (2) were assayed for their cytotoxicity against HeLa and HL60 cells using MTT method.     

Molecular dynamics simulation of [Gd(egta)(H(2)O)](-) in aqueous solution: internal motions of the poly(amino carboxylate) and water ligands, and rotational correlation times

Molecular dynamics simulations of [Gd(egta)(H(2)O)](-) (egta(4-)=3,12-bis(carboxymethyl)-6,9-dioxa-3,12-diazatetradecanedioate(4-)) have been performed without any artificial constraint on the first coordination sphere, such as covalent bonds between the Gd(3+) and the coordination sites. Two new crystallographic structures were determined for this gadolinium chelate and used to start two molecular dynamics simulations. [Gd(egta)(H(2)O)](-) and [Gd(egta)](-) were both observed during the simulations, with a mean volume for the reaction of dissociation [Gd(egta)(H(2)O)](-)-->[Gd(egta)](-)+H(2)O of +7.2 cm(3)mol(-1), which corroborates the previously published experimental value of +10.5 cm(3)mol(-1). Changes in the conformation of the complex with the inversion of several dihedral angles are observed in the simulations independently from the water dissociation. Very fast changes of the third-order rotation axis direction of the Gd(3+) coordination polyhedron (of symmetry D(3h)) are observed during the simulations and are related to the mechanism of electronic relaxation of the complex. Different rotational correlation times (tau(R)) were calculated from the simulations on various observables of the complex. Protons of the inner sphere have different tau(R). The mean tau(R) of the two Gd-HW(HW=hydrogen of water molecule) vectors is 72% lower than tau(R) of the complex, and 75% lower than tau(R) of the vector Gd-OW (OW=oxygen of water molecule). This discrimination of the tumbling rates should be taken into account in future global (17)O NMR, EPR and NMRD (nuclear magnetic relaxation dispersion) data analysis.     

A 1H NMR study of 1,4-bis(N-hexadecyl-N, N-dimethylammonium)butane dibromide/sodium anthranilate system: spherical to rod-shaped transition

The effect of addition of sodium anthranilate to 5 mM micellar solutions of gemini surfactant 1,4-bis(N-hexadecyl-N,N-dimethylammonium)butane dibromide is investigated by ¹H NMR. The solubilization site of anthranilate anion near the micellar surface is inferred. In the micelles, the An⁻ ions intercalate among the surfactant headgroups producing morphological changes.     

Unsymmetrical 1-naphthyltellurium(IV) dihalides: the interplay of Te···Br,C–H···Br and C–H···π interactions in the crystal structure of (1-naphthyl)(4-methylphenyl)tellurium(IV) dibromide

The crystal structure of (1-naphthyl)(4-methyl- phenyl)tellurium(IV) dibromide, the first unsymmetrical naphthyl containing diorganotellurium(IV) dibromide, shows the formation of one-dimensional supramolecular arrays where Te···Br secondary bonds link two parallel rows of molecules in a gear-teethed fashion. The weaker C–H···Br and C–H···π hydrogen bonds play important role in the formation of three-dimensional crystal lattice by cross linking these supramolecular motifs.     

Magnitude and origin of the attraction and directionality of the halogen bonds of the complexes of C6F5X and C6H5X (X = I, Br, Cl and F) with pyridine

The geometries and interaction energies of complexes of pyridine with C₆F₅X, C₆H₅X (X=I, Br, Cl, F and H) and R_FI (R_F=CF₃, C₂F₅ and C₃F₇) have been studied by ab initio molecular orbital calculations. The CCSD(T) interaction energies (E_int) for the C₆F₅X–pyridine (X=I, Br, Cl, F and H) complexes at the basis set limit were estimated to be ?5.59, ?4.06, ?2.78, ?0.19 and ?4.37 kcal mol^?1, respectively, whereas the E_int values for the C₆H₅X–pyridine (X=I, Br, Cl and H) complexes were estimated to be ?3.27, ?2.17, ?1.23 and ?1.78 kcal mol^?1, respectively. Electrostatic interactions are the cause of the halogen dependence of the interaction energies and the enhancement of the attraction by the fluorine atoms in C₆F₅X. The values of E_int estimated for the R_FI–pyridine (R_F=CF₃, C₂F₅ and C₃F₇) complexes (?5.14, ?5.38 and ?5.44 kcal mol^?1, respectively) are close to that for the C₆F₅I–pyridine complex. Electrostatic interactions are the major source of the attraction in the strong halogen bond although induction and dispersion interactions also contribute to the attraction. Short‐range (charge‐transfer) interactions do not contribute significantly to the attraction. The magnitude of the directionality of the halogen bond correlates with the magnitude of the attraction. Electrostatic interactions are mainly responsible for the directionality of the halogen bond. The directionality of halogen bonds involving iodine and bromine is high, whereas that of chlorine is low and that of fluorine is negligible. The directionality of the halogen bonds in the C₆F₅I– and C₂F₅I–pyridine complexes is higher than that in the hydrogen bonds in the water dimer and water–formaldehyde complex. The calculations suggest that the C? I and C? Br halogen bonds play an important role in controlling the structures of molecular assemblies, that the C? Cl bonds play a less important role and that C? F bonds have a negligible impact.     

A novel approach to discuss the viscosity Arrhenius behaviour and to derive the partial molar properties in binary mixtures of N,N-dimethylacetamide with 2-methoxyethanol in the temperature interval (from 298.15 to 318.15) K

Calculation of excess properties in N,N-dimethylacetamide + 2-methoxyethanol binary mixtures at (298.15, 308.15 and 318.15) K from experimental density, viscosity and sound velocity values were presented in previous work. Applications of these experimental values to test different correlation equations as well as their corresponding relative functions were also reported. Considering the quasi-equality between the Arrhenius activation energy Ea and the enthalpy of activation of viscous flow ΔH*, here we can define partial molar activation energy Ea₁ and Ea₂ for N,N-dimethylacetamide and 2-methoxyethanol, respectively, along with their individual contribution separately. Correlation between Arrhenius parameters reveals interesting Arrhenius temperature with a comparison to the vaporisation temperature in the liquid vapour equilibrium, and the limiting corresponding partial molar properties that can permit us to estimate the boiling points of the pure components.     

Solution thermodynamics of first row transition elements. 3. Apparent molal volumes of aqueous ZnCl2 and Zn(CIO4)2 from 15 to 55°C and an examination of solute-solute and solute-solvent interactions

The apparent molal volumes of aqueous ZnCl₂ and Zn(ClO₄)₂ solutions have been measured from 15–55°C. The dilute solution data are extrapolated to infinite dilution using the Redlich-Meyer equation. The full concentration range data are fitted with the Pitzer formalism. The data are then compared with the data on the previously measured salts of Mn²⁺, Fe²⁺, Co²⁺, Ni²⁺, and Cu²⁺. The effect of complex ion formation is easily seen in the Cu²⁺ and Zn²⁺ salt data. A new approach to single ion volumes from salt volumes is proposed. The calculated ionic volumes at infinite dilution are compared, and it is clear that crystal field effects must be considered in any quantitative theory of transition element volumes.     

Structure-defining interactions in the salt cocrystals of [(Me5C5)2Fe]+I3−–XC6H4OH (X = Cl,I): weak noncovalent vs. strong ionic bonding

1. Download : Download high-res image (135KB)
2. Download : Download full-size image

     

Antiferromagnetic spin chain behavior and a transition to 3D magnetic order in Cu(D,L-alanine)2: Roles of H-bonds

We study the spin chain behavior, a transition to 3D magnetic order and the magnitudes of the exchange interactions for the metal-amino acid complex Cu(D,L-alanine)₂∙H₂O, a model compound to investigate exchange couplings supported by chemical paths characteristic of biomolecules. Thermal and magnetic data were obtained as a function of temperature (T) and magnetic field (B₀). The magnetic contribution to the specific heat, measured between 0.48 and 30 K, displays above 1.8 K a 1D spin-chain behavior that can be fitted with an intrachain antiferromagnetic (AFM) exchange coupling constant 2J₀=(−2.12±0.08) cm⁻¹ (defined as ℋ_ex(i,i+1) = −2J₀S_i⋅S_i+1), between neighbor coppers at 4.49 Å along chains connected by non-covalent and H-bonds. We also observe a narrow specific heat peak at 0.89 K indicating a phase transition to a 3D magnetically ordered phase. Magnetization curves at fixed T = 2, 4 and 7 K with B₀ between 0 and 9 T, and at T between 2 and 300 K with several fixed values of B₀ were globally fitted by an intrachain AFM exchange coupling constant 2J₀=(−2.27±0.02) cm⁻¹ and g = 2.091±0.005. Interchain interactions J₁ between coppers in neighbor chains connected through long chemical paths with total length of 9.51 Å cannot be estimated from magnetization curves. However, observation of the phase transition in the specific heat data allows estimating the range 0.1≤|2J₁|≤0.4 cm⁻¹, covering the predictions of various approximations. We analyze the magnitudes of 2J₀ and 2J₁ in terms of the structure of the corresponding chemical paths. The main contribution in supporting the intrachain interaction is assigned to H-bonds while the interchain interactions are supported by paths containing H-bonds and carboxylate bridges, with the role of the H-bonds being predominant. We compare the obtained intrachain coupling with studies of compounds showing similar behavior and discuss the validity of the approximations allowing to calculate the interchain interactions.     

A close inspection of Ag(I) coordination to molecular baskets. A study of solvation and guest encapsulation in solution and the solid state

Four molecular baskets 1-4, each comprising a modular bowl-shaped platform and a set of distinctive aromatic gates, were synthesized. The gates were made to incorporate a nitrogen heteroatom at different positions, as in 2-4, or without a coordinating nitrogen, as in 1 (Fig. 1). For polydentate 3 and 4, the location of the nitrogen was revealed to have an effect on directing the basket's coordination to Ag(I) cation, and subsequent folding to enclose space. The folded geometries were shown to encompass a helical, Ag(I):3, or C_3v/C_2v symmetrical, Ag(I):4, dynamic arrangement of the gates (from density functional theory). For 2 and 1, however, the presence of Ag(I) caused the sole formation of oligomers and the absence of coordinating interactions, respectively. Variable temperature (VT) ¹H and ¹⁹F NMR measurements of Ag(I):3 did not provide direct evidence for the solvation of its inner space and the encapsulation of the BF_4⁻ counterion. Moreover, CH₃CN or CH₃NC substrates were not found inside of Ag(I):3. The finding is in contrast with the behavior of Cu(I):3, which is known to encapsulate these guests. The intriguing guest selectivity was accounted for by small structural and electronic differences of Ag(I)/Cu(I) folded baskets. The X-ray solid-state structural studies of 2, 3, and 4 revealed the basket's capacity to fill its inner space with small compounds. Thus, 3 was found with an ordered molecule of chloroform, while 4 contained molecules of CH₃OH and H₂O. The basket selectivity for enclosing and positioning guests, in the solid state, was deduced to be guided by their size and weak host-guest and guest-guest noncovalent interactions.