•Metallo inorganic rings of Sc, Y, La, Lu, into a phosphazenic ligand.•Structural comparison of Sc, Y, La, and Lu complexes•The flexibility of phosphazenic ligands in rare earth complexes.•Inorganic ...rings containing rare earth cations.•Influence of the ionic radii in the structure of rare earth complexes.
In the present study, we report the synthesis, spectroscopic characterization, and X-ray single crystal structural determination of four rare earth complexes, MPh2P(O)NP(O)PPh23, M = Sc, Y, La, and Lu. The structural study reveals that the Sc, Y, and Lu complexes have coordination numbers of six, while the La complex shows a coordination number of seven, through the presence of the additional coordination of a water molecule with a square-face-capped geometry, where the water molecule enables the formation of a dimeric structure through O-H...O hydrogen bond interactions. The metal ions M3+, Sc, Y, La, and Lu are coordinated to the Ph2P(O)NP(O)Ph2− ligand with a delocalized phosphazenic PNP system in an O,O isobidentate manner, generating carbon-free metallo-inorganic six-membered rings, of which one acquires the a (anti-parallel) conformation and the other two the twist-boat conformation. The Y and Lu complexes crystallized with similar unit cells, M...O distances, and O...M...O angles that are consequences of their similar crystal radii related to the lanthanide contraction in Lu, while the La complex has a coordination number of seven through the coordination of a water molecule and a square-face-capped geometry. The O-M-O angles in the complexes suggest that the bite of the ligand depends on the size of the metal ion, the flexibility, and the steric effects of the tetra-phenyl-imidodiphosphinate ligand.
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•Tetrazole-carboxylates of organotin(IV) were obtained for first occasion.•The reaction of Bargellini is a useful technique for the preparation of new ligands.•Tetrazole-carboxylate complexes have a ...rigid tetrazole and a flexible carboxylate.•X-Ray structures of four organotin(IV) tetrazole-carboxylates were determinated.
The organometallic tin(IV) carboxylates are, in general, well known; however, the corresponding organotin(IV) tetrazole-carboxylates are not known, despite their interest in function of the presence, in these bifunctional ligands, of a rigid tetrazole ring and a flexible carboxylate anion with the possibility of a wide structural diversity and relevant biological activity. In consequence, we report here the synthesis and full characterization of seven new organotin(IV) complexes with a 5-thio-tetrazole carboxylate ligand, the anion of the 2-methyl-2-(1-phenyl-1H-tetrazol-5-yl)sulfanyl)-propanoic acid obtained from the Bargellini reaction. The reaction of Bargellini is a source of economical synthesis of compounds in a multi-component reaction with an increase in complexity and functionality; however, its use in the synthesis of ligands for the obtention of new metal complexes is very limited. Therefore, another reason for this study lies in the convenience of broadly showing the usefulness of this reaction in the synthesis of ligands suitable for coordination chemistry. The new complexes were characterized by common spectroscopic techniques, and elemental analysis, and four of the complexes by single-crystal X-ray diffraction, whose structures are discussed, and the complexes were tested for their antibacterial capacities.
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•Self-assembly of the dithiophosphonate tectons generating supramolecular synthons via NH···S, NH···O, CH···S, CH···O, CH···π, and lp···π interactions.•Connection between molecular and supramolecular ...chirality in the crystalline state (chirogenesis).•NCI index analysis supports the proposition of P-stereogenic centers.•Chiral transference of the p atom to the supramolecular helical assembly.•Spontaneous resolution process to generate the homochiral crystal.
The self-assembly of the dithiophosphonate tectons synthesized in this work generated novel supramolecular synthonsvia NH···S, NH···O, CH···S, CH···O, CH···π, and lp···π interactions. The reaction of the salts with chloro dithiastibocanes X(CH2CH2S)2SbCl (X = O, S) led to the formation of coordination compounds in which the crystal structures showed two new supramolecular synthons stabilized by CH···π and lp···π interactions. The theoretical study of the electronic density of the crystal and their synthons in the solid-state used the robust NCI index to confirm the nature of the interactions found. This study confirmed the connection between molecular and supramolecular chirality in the crystalline state. Three significant features unequivocally support the findings: the role of intramolecular interactions, the electronic density differences among diastereomers, and the nature of trans-annular bonds. The characterization of the salts: ammonium-menthoxy (4-methoxyphenyl) dithiophosphonate (1), triethylammonium-menthoxy (4-methoxyphenyl)-dithiophosphonate (2), triethylammonium-biphenyl-4‑methoxy (4-methoxyphenyl) dithiophosphonate (3), and the coordination compounds O(CH2CH2S)2SbS2P(biphenyl-4‑methoxy)(4-MeOC6H4) (4) and S(CH2CH2S)2SbS2P(biphenyl-4‑methoxy)(4-MeOC6H4) (5) was carried out by elemental analyses, IR, NMR (1H, 13C, 31P), and single-crystal X-ray diffraction analysis.
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•Synthesis of new organotin (IV) complexes derived from (1R, 2S) ephedrinedithiocarbamate ligand.•Antibacterial activity of organotin(IV) ephedrinedithiocarbamate.•Structure of ...organotin(IV) ephedrinedithiocarbamate is in an anisobidentate coordination.
The synthesis of eight new organotin derivatives containing ephedrine-substituted dithiocarbamate ligands R3Sn(ephedtc) 2–5. 2: R = Me; 3: R = Bu; 4: R = Cy; 5: R = Ph and R2Sn(ephdtc)2 6–9. 6: R = Me; 7: R = Bu; 8: R = t-Bu; 9: R = Ph is reported. The complexes were obtained from sodium ephedrinedithiocarbamate Na(ephedtc) 1 and the corresponding tri-organotin(IV) chlorides, R3SnCl 2–5 or di-organotin(IV) dichlorides, R2SnCl26–9. They were characterized by elemental analysis, IR, and NMR spectroscopy (1H, 13C, and 119Sn). The infrared spectra (solid-state) suggest that the Sn(IV) is coordinated to the ligand ephedtc, through the two sulfur atoms in an anisobidentate coordination mode. In solution, the 119Sn NMR indicates the coordination numbers: tetracoordinated for 2–4, pentacoordinate for 5, and hexacoordinated for 6–9. The single-crystal X-ray diffraction analysis of 4 reveals an anisobidentate coordination mode with a trigonal bipyramid distorted geometry around the Sn(IV). All compounds except 2, show inhibition in at least one bacterial strain, and 7 and 9 have the best antibacterial activity, mainly in the clinically isolated strains.
•Three lanthanum(III) 2-amino-1-cyclopentene-1-carbodiothioate (ACDA) were obtained.•It is reported the first structural determinations of a rare earth ACDA complexes.•The ACDA is bonded to the ...lanthanum in a S,S coordination mode.•The DFT calculations for all the ACDA lanthanide complexes is in favor of the S,S mode.
The synthesis and characterization of the first three La(III) 2-amino-1-cyclopentene-1-carbodithioate (ACDA) complexes is reported including two ionic complexes, NEt3HLa(ACDA4) (1), N(n-Bu)4La(ACDA4 (2) and La(ACDA)3)(1,10-phenanthroline) (3). The single-crystal X-ray structures of 1–3 correspond to the first known structural determination of ACDA rare earth complexes. Compounds 1–3 show an S,S coordination mode, and due to hydrogen bonding present in the ligands, secondary interactions were observed. DFT calculations for all the lanthanide series indicate that the ACDA ligand binds in an isobidentate fashion through low covalent M–S bonds, as evidenced by natural population analysis. Furthermore, the S,S coordination mode is overwhelmingly preferred over the N,S coordination, as demonstrated by free energy calculations from the vibrational frequency analysis.
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In the title crystal, the salt CsMe
2
P(S)NP(S)Me
2
is self-assembled as an undulating supramolecular two-dimensional polymeric structure, poly(μ
4
-tetramethyldithioimidodiphosphinato)caesium, Cs(C
...4
H
12
NP
2
S
2
)
n
, which is parallel to the
bc
plane. The Cs cations are hexacoordinated, being chelated by two thioimidophosphinate groups and two sulfur atoms from neighboring ligands. The anions are linked to the Cs cations by Cs...S and Cs...N electrostatic interactions.
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•New cholesteryl dithio-phosphonates of As(III) and Sb(III)•Metallolanes y metallocanes of As(III) and Sb(III) involved in a dithiophosphonate ligand.•Biological activity and DFT ...correlations of dithiophosphonate complexes of As(III) and Sb(III)•Crystal structure of Arsenic and Antimony dithiophosphonates into metalloheterocycles.
The synthesis and characterization of six new O-cholesteryl-dithiophosphonates containing thio-metalloheterocycles of As(III) and Sb(III); (CH2S)2AsS2P(cholesteryl)(4-MeOC6H5) (2), (CH2S)2SbS2P(cholesteryl)(4-MeOC6H5) (3), O(CH2CH2S)2AsS2P(cholesteryl)(4-MeOC6H5) (4), O(CH2CH2S)2SbS2P(cholesteryl)(4-MeOC6H5) (5), S(CH2CH2S)2As S2P(cholesteryl)(4-MeOC6H5) (6), and S(CH2CH2S)2SbS2P(cholesteryl)(4-MeOC6H5) (7) are reported. 2–7 have been prepared from the reaction between the triethylammonium salt of O-3β-cholest-5-en-3-yl (4-methoxyphenyl) dithiophosphonate (1) and five and eight membered chloro-metalloheterocycles of As(III) and Sb(III). The obtained compounds have been characterized by elemental analyses, IR and NMR (1H, 13C, and 31P) spectroscopy. The 31P NMR data suggest that the dithiophosphonate ligand presents, in solution, a bidentate coordination. The structures of 3 and 4 were determined by X-ray single crystal analysis, that correspond to the first examples of such determinations in Group 15 dithiophosphonates, showing an anisobidentate coordination mode of the dithiophosphonate moiety. Sb(III) and As(III) in compounds 3 and 4 present tetracoordination and pentacoordination, respectively. The pentacoordination in 4 is achieved through a 1,5 transannular As⋯O interaction. Antibacterial assays were performed and the activity was correlated with the electronic distribution and molecular shape, employing their geometrical structures, Mulliken partial charges, dipole moments and Molecular Electrostatic Potential maps from DFT calculations.
Intramolecular interactions in (2-CH3OC6H4)CH2MPh3 (M=Group 14) compounds, synthesis, structural and DFT studies.
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•(2-CH3OC6H4)CH2MPh3 M=Si, Ge, Pb were obtained to test the presence ...of O→M interactions.•(2-CH3OC6H4)CH2MPh3 M=Si, Ge have a slightly distorted tetrahedral geometry.•DFT data for (2-CH3OC6H4)CH2MPh3 M=Si, Ge, Sn, Pb indicate the presence of O→M when M=Sn, Pb.
In order to test the possible presence of the intramolecular interactions O→M in the group 14 elements and its consequences on the geometry, the 2-methoxybenzyl chlorine was reacted with magnesium and subsequently with the group 14 chlorides, Ph3MCl, to produce the organometallic compounds (2-CH3OC6H4)CH2MPh3 M=Si (1), Ge (2) and Pb (3). The compounds were fully characterized by elemental analysis, infrared spectroscopy, mass spectrometry (FAB+), and multinuclear (1H, 13C, 29Si, 207Pb) NMR spectroscopy. The compounds 1 and 2 also were investigated by single crystal X-ray diffraction analysis, they are isostructural with a triclinic crystal system and P-1 space group, exhibiting a distorted tetrahedral environment. The possible intramolecular O→M distances in 1 and 2 are 3.810Å and 3.802Å respectively, and represent more than the 100% of the sum of the appropriate Van der Waal’s radii. By comparison, in the previously reported tin analogous compound, that is not part of this work, the intramolecular distance O→Sn is ∼80% of the sum of the Van der Waal’s radii. The molecular structures of the four organometallic complexes were fully studied within the Density Functional Theory formalism.
Reactions of methylamino-N,N-bis(2-methylene-4,6-di-tert-butylphenol) (1) with one or two equivalents of bulk Li, Na or K metals in THF or DMSO render mono or dialkali metal complexes depending on ...the stoichiometric ratio of the reactants. The metal-methylamino-N-(2-methylene-4,6-tert-butylphenol)N-(2-methylene-4,6-tert-butylphenolate) complexes, 2Li, 2Na and 2K, are generated upon the substitution of a single phenol hydrogen of 1. In the solid state, complex 2Na is a dimer due to the establishment of two symmetric hydrogen bonds between two adjacent molecules. The Na center also engages into the formation of a ten-membered metallacycle ring with a butterfly-like structure. Due to dimerization, an intermolecular six-membered core is formed involving two sodium and four oxygen atoms. The weakly coordinated nitrogen atom from the ligand is nearly perpendicular to the hexagonal core. The dimetal-methylamino-N,N′-bis(2-methylene-4,6-di-tert-butylphenolate) complexes, 3Li, 3Na and 3K result from metal substitution of the two phenol hydrogens from ligand 1. The SC-XRD structures of 3Li and 3Na are discreet, each incorporating two metal atoms in different coordination environments. Ten-membered rings with boat-boat conformations are also observed as are rhombic central M2O2 cores. The molecular structure of 3K in DMSO shows a higher degree of aggregation. It effectively comprises four K atoms, two ligand backbones and seven solvent molecules forming a central four-membered K2O2 ring perpendicular to an eight-membered structure formed also by K and O atoms spanning over the two ligand moieties.
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•Stoichiometric control allows the synthesis of mono or dialkalimetal complexes.•In the solid state, dimer 2Na is formed by symmetric intermolecular hydrogen bonds.•3Li and 3Na form ten-membered rings and have rhombic central M2O2 cores.•3K has a central K2O2 ring perpendicular to an eight-membered structure.
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