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1.
Int J Mol Sci ; 24(19)2023 Sep 27.
Artigo em Inglês | MEDLINE | ID: mdl-37834088

RESUMO

We designed 0D, 1D, and 2D supramolecular assemblies made of diaryliodonium salts (functioning as double σ-hole donors) and carboxylates (as σ-hole acceptors). The association was based on two charge-supported halogen bonds (XB), which occurred between IIII sites of the iodonium cations and the carboxylate anions. The sequential introduction of the carboxylic groups in the aryl ring of the benzoic acid added a dimension to the 0D supramolecular organization of the benzoate, which furnished 1D-chained and 2D-layered structures when terephthalate and trimesate anions, correspondingly, were applied as XB acceptors. The structure-directing XB were studied using DFT calculations under periodic boundary conditions and were followed by the one-electron-potential analysis and the Bader atoms-in-molecules topological analysis of electron density. These theoretical methods confirmed the existence of the XB and verified the philicities of the interaction partners in the designed solid-state structures.


Assuntos
Ácidos Carboxílicos , Halogênios , Halogênios/química , Ânions , Teoria da Densidade Funcional , Ácido Benzoico
2.
Org Biomol Chem ; 21(33): 6743-6749, 2023 Aug 23.
Artigo em Inglês | MEDLINE | ID: mdl-37552120

RESUMO

We developed an atom- and reaction mass efficient strategy for the preparation of diarylselenides using iodonium salts as reactants. The developed approach allows the obtaining of diarylselenides from the corresponding trimethoxyphenyl-substituted iodonium salts via a two-step one-pot reaction sequence. The proposed metal-free methodology is based on the involvement of both iodonium aryl groups for diarylation.

3.
Inorg Chem ; 62(15): 6128-6137, 2023 Apr 17.
Artigo em Inglês | MEDLINE | ID: mdl-37000904

RESUMO

Five new copper(I) complexes─composed of the paired dibenzohalolium and [CuL2]- (L = 1,2,4-oxadiazolate) counterions in which O,O-atoms of the anion are simultaneously linked to the halogen atom─were generated and isolated as the solid via the three-component reaction between [Cu(MeCN)4](BF4), sodium 1,2,4-oxadiazolates, and dibenzohalolium triflates (or trifluoroacetates). This reaction is different from the previously reported CuI-catalyzed arylation of 1,2,4-oxadiazolones by diaryliodonium salts. Inspection of the solid-state X-ray structures of the complexes revealed the strong three-center X···O,O (X = Br, I) halogen bonding occurred between the oxadiazolate moieties and dibenzohalolium cation. According to performed theoretical calculations, this noncovalent interaction (or noncovalent chelation) was recognized as the main force in the stabilization of the copper(I) complexes. An explanation for the different behavior of complexes, which provide either chelate or nonchelate binding, is based on the occurrence of additional -CH3···π interactions, which were also quantified.

4.
Int J Mol Sci ; 23(19)2022 Oct 06.
Artigo em Inglês | MEDLINE | ID: mdl-36233178

RESUMO

The co-crystallization of the lead(II) complex [Pb(S2CNEt2)2] with tetraiodoethylene (C2I4) gave the co-crystal, [Pb(S2CNEt2)2]∙½C2I4, whose X-ray structure exhibits only a small change of the crystal parameters than those in the parent [Pb(S2CNEt2)2]. The supramolecular organization of the co-crystal is largely determined by an interplay between Pb⋯S tetrel bonding (TeB) and I⋯S halogen bonding (HaB) with comparable contributions from these non-covalent contacts; the TeBs observed in the parent complex, [Pb(S2CNEt2)2], remain unchanged in the co-crystal. An analysis of the theoretical calculation data, performed for the crystal and cluster models of [Pb(S2CNEt2)2]∙½C2I4, revealed the non-covalent nature of the Pb⋯S TeB (-5.41 and -7.78 kcal/mol) and I⋯S HaB (-7.26 and -11.37 kcal/mol) interactions and indicate that in the co-crystal these non-covalent forces are similar in energy.


Assuntos
Ditiocarb , Halogênios , Halogênios/química , Hidrocarbonetos Iodados , Chumbo , Modelos Moleculares
5.
ACS Omega ; 7(38): 34454-34462, 2022 Sep 27.
Artigo em Inglês | MEDLINE | ID: mdl-36188282

RESUMO

Cyclometalated platinum(II) complexes [Pt(ppy)Cl(CNAr)] (ppy = 2-phenylpyridinato-C2,N; Ar = C6H4-2-I 1, C6H4-4-I 2, C6H3-2-F-4-I 3, and C6H3-2,4-I2 4) bearing ancillary isocyanide ligands were obtained by the bridge-splitting reaction between the dimer [Pt(ppy)(µ-Cl)]2 and 2 equiv any one of the corresponding CNAr. Complex 2 was crystallized in two polymorphic forms, namely, 2 I and 2 II, exhibiting green (emission quantum yield of 0.5%) and orange (emission quantum yield of 12%) phosphorescence, respectively. Structure-directing non-covalent contacts in these polymorphs were verified by a combination of experimental (X-ray diffraction) and theoretical methods (NCIplot analysis, combined electron localization function (ELF), and Bader quantum theory of atoms in molecules (QTAIM analysis)). A noticeable difference in the spectrum of non-covalent interactions of 2 I and 2 II is seen in the Pt···Pt interactions in 2 II and absence of these metallophilic contacts in 2 I. The other solid luminophores, namely, 1, 3 I-II, 4, and 4·CHCl3, exhibit green luminescence; their structures include intermolecular C-I···Cl-Pt halogen bonds as the structure-directing interactions. Crystals of 1, 2 I, 3 I, 3 II, 4, and 4·CHCl3 demonstrated a reversible mechanochromic color change achieved by mechanical grinding (green to orange) and solvent adsorption (orange to green).

6.
Chemistry ; 28(70): e202201869, 2022 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-36178324

RESUMO

The co-crystallization of tetracyanobenzene (TCB) with haloarenes ArX provided six new co-crystals TCB ⋅ ArX (ArX=PhCl, PhBr, 4-MeC6 H4 Cl, 4-MeC6 H4 Br, 4-MeOC6 H4 Cl, 1,2-Br2 C6 H4 ) which were studied by X-ray diffraction. In these systems, the strong collective effect of π⋅⋅⋅π stacking interactions and lone pair-(X)⋅⋅⋅π-hole-(C) bondings between TCB and ArX promote the strength of X⋅⋅⋅Ncyano halogen bonding (HaB). Theoretical studies showed that the stacking interactions affect the σ-hole depth of the haloarenes, thus significantly boosting their ability to function as HaB donors. According to the molecular electrostatic potential calculations, the σ- hole-(Cl) value (1.5 kcal/mol) in the haloarene 4-MeOC6 H4 Cl (featuring an electron-rich arene moiety and exhibiting very poor σ-hole-(Cl) ability) increases significantly in the stacked trimer (TCB)2 ⋅ 4-MeOC6 H4 Cl (12.5 kcal/mol). Theoretical DFT calculations demonstrate the dramatic increase of X⋅⋅⋅Ncyano HaB strength for stacked trimers in comparison with parent unstacked haloarenes.

7.
Inorg Chem ; 61(39): 15398-15407, 2022 Oct 03.
Artigo em Inglês | MEDLINE | ID: mdl-36137295

RESUMO

A single-crystal X-ray diffraction (XRD) study of diaryliodonium tetrachloroaurates (or, in the recent terminology, tetrachloridoaurates), [(p-XC6H4)2I][AuCl4] (X = Cl, 1; Br, 2), was performed for 1 (the structure is denoted as 1a to show similarity with the isomorphic structure 2a) and two polymorphs─2a (obtained from MeOH) and 2b (from 1,2-C2H4Cl2). Examination of the XRD data for these three structures revealed 2-center C-X···AuIII (X = Cl and Br) and 3-center bifurcated C-Br···(Cl-Au) halogen bonding (abbreviated as XB) between the p-Cl or p-Br atoms of the diaryliodonium cations and the gold(III) atom of [AuCl4]-. The noncovalent nature of AuIII-involving interactions, the nucleophilicity of the gold(III) atoms, and the electrophilic role of p-X atoms of the diaryliodonium cations in the XBs were studied by a set of complementary computational methods. Combined experimental and theoretical studies allowed the recognition of the d-nucleophilicity of the [d8AuIII] atom which, regardless of its rather substantial formal 3+ charge, can function as a d-nucleophilic partner of XB. This conclusion was also supported by theoretical calculations performed for the structures' refcodes BINXOM and ICSD 62511; the obtained data verified the nucleophilicity of AuIII toward a K+ ions or a σ-(Cl)-hole, respectively. All our results, together with consideration of relevant literature, indicate that gold atoms in the three oxidation states (0, I, and even III) exhibit nucleophilicity in XBs.

8.
Molecules ; 27(15)2022 Jul 28.
Artigo em Inglês | MEDLINE | ID: mdl-35956799

RESUMO

In this study, we present results of a detailed topological analysis of electron density (ED) of 145 halogen-bonded complexes formed by various fluorine-, chlorine-, bromine-, and iodine-containing compounds with trimethylphosphine oxide, Me3PO. To characterize the halogen bond (XB) strength, we used the complexation enthalpy, the interatomic distance between oxygen and halogen, as well as the typical set of electron density properties at the bond critical points calculated at B3LYP/jorge-ATZP level of theory. We show for the first time that it is possible to predict the XB strength based on the distance between the minima of ED and molecular electrostatic potential (ESP) along the XB path. The gap between ED and ESP minima exponentially depends on local electronic kinetic energy density at the bond critical point and tends to be a common limiting value for the strongest halogen bond.

9.
Chem Sci ; 13(19): 5650-5658, 2022 May 18.
Artigo em Inglês | MEDLINE | ID: mdl-35694330

RESUMO

Porous architectures characterized by parallel channels arranged in honeycomb or rectangular patterns are identified in two polymorphic crystals of a zwitterionic 4-(aryliodonio)-benzenesulfonate. The channels are filled with disordered water molecules which can be reversibly removed on heating. Consistent with the remarkable strength and directionality of the halogen bonds (XBs) driving the crystal packing formation, the porous structure is stable and fully preserved on almost quantitative removal and readsorption of water. The porous systems described here are the first reported cases of one-component 3D organic frameworks whose assembly is driven by XB only (XOFs). These systems are a proof of concept for the ability of zwitterionic aryliodonium tectons in affording robust one-component 3D XOFs. The high directionality and strength of the XBs formed by these zwitterions and the geometrical constraints resulting from the tendency of their hypervalent iodine atoms to act as bidentate XB donors might be key factors in determining this ability.

10.
Inorg Chem ; 61(5): 2558-2567, 2022 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-35073483

RESUMO

Three isomorphic cocrystals were obtained via the crystallization of [PPN][AuCl2] (1) from CHBr3 (1·CHBr3), or CHCl3/1,2-C2F4Br2 (1·CHCl3) and CH2Cl2/Et2O (1·CH2Cl2) mixtures. Analysis of the single-crystal X-ray diffraction data for these cocrystals revealed a gold(I)-involving two-center C-X···Au halogen bond (abbreviated as XB; X = Cl, Br) and a three-center bifurcated C-Br···(Cl-Au) XB; in the latter, the gold(I)-chloride linkage functions as an integrated XB acceptor. The noncovalent nature and energies [spanning from -1.58 to -5.52 kcal/mol for C-X···Au and -6.37 kcal/mol for C-Br···(Cl-Au) XBs] of these noncovalent interactions were studied by density functional theory calculations and topological analysis of the electron density distribution in the framework of the quantum theory of atoms-in-molecules (QTAIM) followed by noncovalent interaction (NCI) analysis at the B3LYP-D3/jorge-TZP-DKH level of theory. The nucleophilicity of the gold(I) centers toward halogens of halomethanes was verified by a set of independent methods including electrostatic potential surfaces, electron localization function projection, natural bond orbital charge transfer, electron density/electrostatic potential profile, Wiberg bond indexes, natural population analysis, and atoms-in-molecules charge analyses.

11.
Chemistry ; 28(2): e202103173, 2022 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-34623005

RESUMO

This review highlights recent studies discovering unconventional halogen bonding (HaB) that involves positively charged metal centers. These centers provide their filled d-orbitals for HaB, and thus behave as nucleophilic components toward the noncovalent interaction. This role of some electron-rich transition metal centers can be considered an oxymoron in the sense that the metal is, in most cases, formally cationic; consequently, its electron donor function is unexpected. The importance of Ha⋅⋅⋅d-[M] (Ha=halogen; M is Group 9 (Rh, Ir), 10 (Ni, Pd, Pt), or 11 (Cu, Au)) interactions in crystal engineering is emphasized by showing remarkable examples (reported and uncovered by our processing of the Cambridge Structural Database), where this Ha⋅⋅⋅d-[M] directional interaction guides the formation of solid supramolecular assemblies of different dimensionalities.

12.
JACS Au ; 1(3): 354-361, 2021 Mar 22.
Artigo em Inglês | MEDLINE | ID: mdl-34467299

RESUMO

The complexes [RhX(COD)]2 (X = Cl, Br; COD = 1,5-cyclooctadiene) form cocrystals with σ-hole iodine donors. X-ray diffraction studies and extensive theoretical considerations indicate that the d z 2-orbitals of two positively charged rhodium(I) centers provide sufficient nucleophilicity to form a three-center halogen bond (XB) with the σ-hole donors. The two metal centers function as an integrated XB acceptor, providing assembly via a metal-involving XB.

13.
Inorg Chem ; 60(17): 13200-13211, 2021 Sep 06.
Artigo em Inglês | MEDLINE | ID: mdl-34357775

RESUMO

Two isostructural trans-[MI2(CNXyl)2]·I2 (M = Pd or Pt; CNXyl = 2,6-dimethylphenyl isocyanide) metallopolymeric cocrystals containing uncommon bifurcated iodine···(metal-iodide) contact were obtained. In addition to classical halogen bonding, single-crystal X-ray diffraction analysis revealed a rare type of metal-involved stabilizing contact in both cocrystals. The nature of the noncovalent contact was studied computationally (via DFT, electrostatic surface potential, electron localization function, quantum theory of atoms in molecules, and noncovalent interactions plot methods). Studies confirmed that the I···I halogen bond is the strongest noncovalent interaction in the systems, followed by weaker I···M interaction. The electrophilic and nucleophilic nature of atoms participating in I···M interaction was studied with ED/ESP minima analysis. In trans-[PtI2(CNXyl)2]·I2 cocrystal, Pt atoms act as weak nucleophiles in I···Pt interaction. In the case of trans-[PdI2(CNXyl)2]·I2 cocrystal, electrophilic/nucleophilic roles of Pd and I are not clear, and thus the quasimetallophilic nature of the I···Pd interaction was suggested.

14.
Chem Asian J ; 16(11): 1445-1455, 2021 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-33844884

RESUMO

An interplay between 4-bromo- and 4-iodo-5-nitrophthalonitriles (XNPN, X=Br or I) and any one of the azines (pyridine 1, 4-dimethylaminopyridine 2, isoquinoline 3, 4-cyanopyridine 4, 2-methylpyridine 5, 2-aminopyridine 6, quinoline 7, 1-methylisoquinoline 8, and 2,2'-bipyridine 9) proceeds differently depending on steric and electronic effects of the heterocycles. Sterically unhindered azines 1-3 underwent N-arylation to give the corresponding azinium salts (characterized by 1 H and 13 C{H} NMR and high-resolution ESI-MS). In contrast, azines 4-9 with sterically hindered N atoms or bearing an electron-withdrawing substituent, form stable co-crystals with XNPN, where two interacting molecules are bound by halogen bonding. In all obtained co-crystals, X⋅⋅⋅N structure-directed halogen bonds were recognized and theoretically evaluated including DFT calculations (PBE0-D3/def2-TZVP level of theory), QTAIM analysis, molecular electrostatic potential surfaces, and noncovalent interaction plot index. Estimated energies of halogen bonding vary from -7.6 kcal/mol (for 6 ⋅ INPN) to -11.4 kcal/mol (5 ⋅ INPN).

15.
Molecules ; 25(6)2020 Mar 19.
Artigo em Inglês | MEDLINE | ID: mdl-32204523

RESUMO

An extensive series of 128 halogen-bonded complexes formed by trimethylphosphine oxide and various F-, Cl-, Br-, I- and At-containing molecules, ranging in energy from 0 to 124 kJ/mol, is studied by DFT calculations in vacuum. The results reveal correlations between R-X⋅⋅⋅O=PMe3 halogen bond energy ΔE, X⋅⋅⋅O distance r, halogen's σ-hole size, QTAIM parameters at halogen bond critical point and changes of spectroscopic parameters of phosphine oxide upon complexation, such as 31P NMR chemical shift, ΔδP, and P=O stretching frequency, Δν. Some of the correlations are halogen-specific, i.e., different for F, Cl, Br, I and At, such as ΔE(r), while others are general, i.e., fulfilled for the whole set of complexes at once, such as ΔE(ΔδP). The proposed correlations could be used to estimate the halogen bond properties in disordered media (liquids, solutions, polymers, glasses) from the corresponding NMR and IR spectra.


Assuntos
Halogênios/química , Fosfinas/química , Teoria da Densidade Funcional , Espectroscopia de Ressonância Magnética , Modelos Moleculares , Eletricidade Estática
16.
Inorg Chem ; 59(4): 2316-2327, 2020 Feb 17.
Artigo em Inglês | MEDLINE | ID: mdl-32027131

RESUMO

Reinvestigation of (o-benzoquinonedioximate)2Ni/I2 systems demonstrated that the reaction itself and also the crystallization conditions dramatically affect the identity of generated species. Crystallization (CHCl3, 20-25 °C) of the nickel(II) dioximate complex [Ni(bqoxH)2] (bqoxH2 = o-benzoquinonedioxime) with I2 in the 1:(1-10) molar ratios of the reactants led to several (o-benzoquinonedioximate)2Ni derivatives and/or iodine adducts [Ni(I)(bqoxH)(bqoxH2)]·3/2I2, [Ni(I3)(bqoxH)(bqoxH2)]·[Ni(bqoxH)2], and [Ni(I3)(bqox•-)(bqoxH2)]·I2; the latter one, featuring the anion-radical bqox•- ligand, is derived from the formal (-2H+/1e-)-oxidation of bqoxH2. In these three adducts, various types of noncovalent interactions were identified experimentally and their existence was supported theoretically. The [Ni(I3)(bqox•-)(bqoxH2)]·I2 adduct exhibits simultaneous semicoordination and coordination patterns of the triiodide ligand; this is the first recognition of the semicoordination of any polyiodide ligand to a metal center. The semicoordination noncovalent contact Ni···I3 (3.7011(10) Å) is substantially longer that the Ni-I3 coordination bond (2.8476(9) Å), and the difference in energies between these two types of linkages is 8-12 kcal/mol.

17.
Dalton Trans ; 49(2): 356-367, 2020 Jan 02.
Artigo em Inglês | MEDLINE | ID: mdl-31825414

RESUMO

Hexaiododiplatinates(ii) bearing ammonium and phosphonium cations, [R4N]2[Pt2(µ-I)2I4] {R = Et (1) and n-Bu (2)} and [R3PR1]2[Pt2(µ-I)2I4] {R = n-Bu and R1 = n-Bu (3); R = Ph and R1 = Ph (4); R = Ph and R1 = CH2Ph (5)}, were synthesized and characterized by high resolution ESI-MS, 1H, 13C{1H}, 31P{1H}, and 195Pt NMR spectroscopy, Fourier transform infrared and Raman spectroscopy, X-ray diffraction (XRD), X-ray powder diffraction, and also electrostatic surface potential calculations. Complexes 1-3 were cocrystallized with halogen bond (XB) donors based on organic iodides featuring electron withdrawing groups {REWGIs: 1,3,5-triiodotrifluorobenzene (1,3,5-FIB), iodopentafluorobenzene (IPFB), 1,4-diiodotetrafluorobenzene (1,4-FIB), and tetraiodoethylene (C2I4)} to give crystalline adducts 1·2(1,3,5-FIB), 1·2IPFB, 2·2(1,4-FIB), and 3·C2I4. Inspection of the XRD data of the obtained adducts revealed the presence, in all four structures, of intermolecular REWGII-Pt XBs between the iodine centers of REWGIs and the terminal iodide ligands of [Pt2(µ-I)2I4]2- anions, where the latter act as rectangular XB-accepting synthons forming XBs with two, three, and even four Pt-Iterminal ligands. The results of Hirshfeld molecular surface analysis and density functional theory (DFT) calculations (the M06/DZP-DKH level of theory) followed by topological analysis of the electron density distribution within the framework of Bader's approach (QTAIM) confirmed the existence of the detected XBs, and their estimated energies vary from 2.2 to 4.7 kcal mol-1.

18.
Chem Asian J ; 14(21): 3915-3920, 2019 Nov 04.
Artigo em Inglês | MEDLINE | ID: mdl-31550070

RESUMO

The dihalomethanes CH2 X2 (X=Cl, Br, I) were co-crystallized with the isocyanide complexes trans-[MXM 2 (CNC6 H4 -4-XC )2 ] (M=Pd, Pt; XM =Br, I; XC =F, Cl, Br) to give an extended series comprising 15 X-ray structures of isostructural adducts featuring 1D metal-involving hexagon-like arrays. In these structures, CH2 X2 behave as bent bifunctional XB/XB-donating building blocks, whereas trans-[MXM 2 (CNC6 H4 -4-XC )2 ] act as a linear XB/XB acceptors. Results of DFT calculations indicate that all XCH2 -X⋅⋅⋅XM -M contacts are typical noncovalent interactions with estimated strengths in the range of 1.3-3.2 kcal mol-1 . A CCDC search reveals that hexagon-like arrays are rather common but previously overlooked structural motives for adducts of trans-bis(halide) complexes and halomethanes.

19.
Chemistry ; 25(60): 13671-13675, 2019 Oct 28.
Artigo em Inglês | MEDLINE | ID: mdl-31232494

RESUMO

The isocyanide trans-[PdBr2 (CNC6 H4 -4-X')2 ] (X'=Br, I) and nitrile trans-[PtX2 (NCC6 H4 -4-X')2 ] (X/X'=Cl/Cl, Cl/Br, Br/Cl, Br/Br) complexes exhibit similar structural motif in the solid state, which is determined by hitherto unreported four-center nodes formed by cyclic halogen bonding. Each node is built up by four Type II C-X'⋅⋅⋅X-M halogen-bonding contacts and include one Type I M-X⋅⋅⋅X-M interaction, thus giving the rhombic-like structure. These nodes serve as supramolecular synthons to form 2D layers or double chains of molecules linked by a halogen bond. Results of DFT calculations indicate that all contacts within the nodes are typical noncovalent interactions with the estimated strengths in the range 0.6-2.9 kcal mol-1 .

20.
Angew Chem Int Ed Engl ; 58(13): 4164-4168, 2019 Mar 22.
Artigo em Inglês | MEDLINE | ID: mdl-30667579

RESUMO

The complexes [Pt(tpp)] (H2 tpp=tetraphenylporphyrin), [M(acac)2 ] (M=Pd, Pt, Hacac=acetylacetone), and [Pd(ba)2 ] (Hba=benzoylacetone) were co-crystallized with highly electron-deficient arene systems to form reverse arene sandwich structures built by π-hole⋅⋅⋅[MII ] (d8 M=Pt, Pd) interactions. The adduct [Pt(tpp)]⋅2 C6 F6 is monomeric, whereas the diketonate 1:1 adducts form columnar infinity 1D-stack assembled by simultaneous action of both π-hole⋅⋅⋅[MII ] and C⋅⋅⋅F interactions. The reverse sandwiches are based on noncovalent interactions and calculated ESP distributions indicate that in π-hole⋅⋅⋅[MII ] contacts, [MII ] plays the role of a nucleophile.

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