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1.
Acta Crystallogr E Crystallogr Commun ; 79(Pt 5): 478-481, 2023 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-37151829

RESUMO

The mol-ecular and crystal structure of the title binuclear Zn2+ complex, [Zn2(C8H13O3)4(C2H5OH)2], with enolated anionic tert-butyl-aceto-acetate and ethanol was analysed. The coordination polyhedra of the Zn atoms are distorted octa-hedra formed by six oxygen atoms that belong to three ligand mol-ecules and a coordinated ethanol mol-ecule. In the crystal phase, alternating layers can be distinguished parallel to the ac plane. A Hirshfeld surface analysis showed that there are no strong inter-molecular inter-actions in the structure. The most significant contributions to the overall crystal packing are from H⋯H inter-molecular contacts.

2.
Acta Crystallogr E Crystallogr Commun ; 79(Pt 2): 70-73, 2023 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-36793400

RESUMO

The caesium salt of dimethyl-N-benzoyl-amido-phosphate, namely, aqua-[di-meth-yl (N-benzoyl-amido-κO)phospho-nato-κO]caesium, [Cs(C9H11NO4P)(H2O)] or CsL·H2O, is reported. The compound crystallizes in the monoclinic crystal system in the P21/c space group and forms a mono-periodic polymeric structure due to the bridging function of the dimethyl-N-benzoyl-amido-phosphate anions towards the caesium cations.

3.
Acta Crystallogr E Crystallogr Commun ; 79(Pt 12): 1218-1222, 2023 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-38313130

RESUMO

The tetra-kis complex of neodymium(III), tetra-kis-{µ-N-[bis-(pyrrolidin-1-yl)phos-phor-yl]acet-am-id-ato}bis(pro-pan-2-ol)neodymiumsodium pro-pan-2-ol monosol-vate, [NaNd(C10H16Cl3N3O2)4(C3H8O)2]·C3H8O or NaNdPyr4(i-PrOH)2·i-PrOH, with the amide type CAPh ligand bis(N,N-tetra-methylene)(tri-chloro-acetyl)phos-phoric acid tri-amide (HPyr), has been synthesized, crystallized and characterized by X-ray diffraction. The complex does not have the tetra-kis-(CAPh)lanthanide anion, which is typical for ester-type CAPh-based coordin-ation compounds. Instead, the NdO8 polyhedron is formed by one oxygen atom of a 2-propanol mol-ecule and seven oxygen atoms of CAPh ligands in the title compound. Three CAPh ligands are coordinated in a bidentate chelating manner to the NdIII ion and simultaneously binding the sodium cation by µ2-bridging PO and CO groups while the fourth CAPh ligand is coordinated to the sodium cation in a bidentate chelating manner and, due to the µ2-bridging function of the PO group, also binds the neodymium ion.

4.
Chemphyschem ; 23(14): e202200129, 2022 07 19.
Artigo em Inglês | MEDLINE | ID: mdl-35536851

RESUMO

New lanthanide dimethyl-N-benzoylamidophosphate (HL) based tetrakis-complexes NEt4 [LnL4 ] (Ln3+ =La, Nd, Sm, Eu, Gd, Tb, Dy) are reported. The complexes are characterized by means of NMR, IR, absorption, and luminescent spectroscopy as well as by elemental, X-Ray, and thermal gravimetric analyses. The phenyl groups of the four ligands of the complex anion are directed towards one side, while the methoxy groups are directed in the opposite side, which makes the complexes under consideration structurally similar to calixarenes. The effect of changing the alkali metal counterion to the organic cation NEt4+ on the structure and properties of the tetrakis-complex [LnL4]- is analyzed. The complexes exhibit bright characteristic for respective lanthanides luminescence. Rather high intensity of the band of 5 D0 →7 F4 transition, observed in the luminescence spectrum of NEt4 [EuL4 ], is discussed based on theoretical calculations.


Assuntos
Elementos da Série dos Lantanídeos , Elementos da Série dos Lantanídeos/química , Ligantes , Luminescência , Imageamento por Ressonância Magnética , Espectroscopia de Ressonância Magnética
5.
Acta Crystallogr E Crystallogr Commun ; 77(Pt 12): 1285-1288, 2021 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-34925899

RESUMO

The title compound, 19 H,79 H-3,5,9,11-tetra-oxa-1,7(2,7)-difluorena-4,10(1,3)-dibenzena-cyclo-dodeca-phane-19,79-dione (fluorenonophane), exists as a solvate with chloro-benzene, C42H28O6·C6H5Cl. The fluorenonophane contains two fluorenone fragments linked by two m-substituted benzene fragments. Some decrease in its macrocyclic cavity leads to a stacking inter-action between the tricyclic fluorenone fragments. In the crystal, the fluorenonophane and chloro-benzene mol-ecules are linked by weak C-H⋯π(ring) inter-actions and C-H⋯Cl hydrogen bonds. The Cl atom of chloro-benzene does not form a halogen bond. A Hirshfeld surface analysis and two-dimensional fingerprint plots were used to analyse the inter-molecular contacts found in the crystal structure.

6.
Acta Crystallogr E Crystallogr Commun ; 77(Pt 12): 1307-1310, 2021 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-34925904

RESUMO

The anionic tetra-kis-complex of lanthanum(III) NMe4LaL 4 with the CAPh-ligand dimethyl (2,2,2-tri-chloro-acet-yl)phospho-ramidate (HL), namely, tetra-methyl-ammonium tetra-kis-{2,2,2-tri-chloro-1-[(di-meth-oxy-phosphor-yl)imino]-ethano-lato}lanthanum(III), (C4H12N)[La(C4H6Cl3NO4P)4], has been synthesized, crystallized and structurally characterized by X-ray diffraction. The lanthanide ion is surrounded by four anionic, bis-chelating CAPh ligands forming the complex anion with a coordination number of eight for La3+ and NMe4 + as the counter-ion. The coordination polyhedron of the La3+ ion was inter-preted as a triangular dodeca-hedron.

7.
Acta Crystallogr E Crystallogr Commun ; 77(Pt 9): 950-954, 2021 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-34584768

RESUMO

The asymmetric unit of the title compound, [Co(C12H8N2)2(H2O)2]2[Ge(C6H5O7)2](NO3)2, features two complex [(C12H8N2)2(H2O)2Co]2+ cations, two NO3 - anions as well as one centrosymmetric [(C6H5O7)2Ge]2- anion. Two HCit ligands (Cit = citrate, C6H4O7) each coordinate via three different oxygen atoms (hy-droxy-late, α-carboxyl-ate, ß-carboxyl-ate) to the Ge atom, forming a slightly distorted octa-hedron. The coordination polyhedron of the Co atom is also octa-hedral, formed by coordination of four nitro-gen atoms from two phenanthroline mol-ecules and two water oxygen atoms. In the crystal, the cations and anions are linked by hydrogen bonds and form layers parallel to the bc plane. The structure exhibits disorder of the NO3 - anion [disorder ratio 0.688 (9) to 0.312 (9)]. There are also highly disordered solvent mol-ecules (presumably water and/or ethanol) in the crystal structure; explicit refinement of these mol-ecules was not possible, and the content of the voids was instead taken into account using reverse Fourier transform methods [SQUEEZE procedure in PLATON; Spek (2015 ▸). Acta Cryst. C71, 9-18]. The given chemical formula and other crystal data do not take into account the unknown solvent mol-ecule(s).

8.
Chirality ; 33(10): 722-730, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-34431566

RESUMO

Inherently chiral dialkyloxy-calix[4]arene acetic acids with asymmetric placement of substituents on the lower rim of the macrocycle were first studied as enantiodiscriminating additives to the mobile phase MeCN/H2 O/HCOOH (75/25/0.02 by volume) in the high-performance liquid chromatography (HPLC) separation of d,l-alanine and d,l-valine on the achiral stationary phase ZORBAX Original CN. The dependence of enantio-binding properties on the position of alkyl groups is demonstrated. The highest resolution (1.65) and enantioselectivity (1.80) were obtained for the 1,2-dipropyloxy-calix[4]arene acetic acid.


Assuntos
Acetatos , Aminoácidos , Calixarenos , Cromatografia Líquida de Alta Pressão , Fenóis , Estereoisomerismo
9.
RSC Adv ; 10(42): 24808-24816, 2020 Jun 29.
Artigo em Inglês | MEDLINE | ID: mdl-35517439

RESUMO

The novel bis-chelating carbacylamidophosphate type ligand, tetramethyl[pyridine-2,6-diyldi(iminocarbonyl)]diamidophosphate (H2L), and its sodium salt, NaHL, have been synthesized and their structural properties have been investigated. Coordination compounds of lanthanides [Ln(HL)2NO3]·i-PrOH (Ln = Eu3+, Tb3+) were obtained for the first time, isolated in the individual state and characterized by means of IR and NMR spectroscopies, electrospray ionization mass spectrometry (ESI-MS), potentiometric titration, and elemental, thermal gravimetric and X-ray diffraction analyses. It was shown that H2L behaves like a scorpionate type ligand and in a mono-deprotonated form coordinates in a tridentate manner via the oxygen atoms of phosphoryl and carbonyl groups with formation of a mononuclear metal complex. The protonation constants of H2L and stability constants of Eu3+ and Tb3+ complexes have been determined. According to the results of X-ray diffraction analysis the H2L and [Ln(HL)2NO3]·i-PrOH molecules have monomeric structure but NaHL is a dimer. The Hirshfeld surface and fingerprint plots of the compounds have been used to analyze various hydrogen bonds and intermolecular interactions displayed in the crystal structure.

10.
Beilstein J Org Chem ; 15: 2390-2397, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31666873

RESUMO

The three-component reaction of 5-aminotetrazole with aliphatic aldehydes (formaldehyde, acetaldehyde) and acetoacetic ester derivatives in water under microwave irradiation leads to the selective formation of 4,7-dihydrotetrazolo[1,5-a]pyrimidine derivatives. Under similar conditions using 4,4,4-trifluoroacetoacetic ester 5-hydroxy-4,5,6,7-tetrahydrotetrazolo[1,5-a]pyrimidines are obtained. The analogous reaction with acetylacetone requires scandium(III) triflate as catalyst. The antioxidant activity of selected compounds was assayed with 1,1-diphenyl-2-picrylhydrazyl.

11.
Inorg Chem ; 58(21): 14682-14692, 2019 Nov 04.
Artigo em Inglês | MEDLINE | ID: mdl-31647223

RESUMO

A series of pentanuclear lanthanide complexes Ln5L6(µ-L)4(µ3-OH)4(µ4-OH) (LnIII = Nd, Dy, Ho, Er, Yb; L- = dimethyl N-benzoylamidophosphate ion, [C6H5C(O)-N-P(O)(OCH3)2]-) was obtained by the reaction of sodium dimethyl N-benzoylamidophosphate with the corresponding lanthanide nitrates. The pentanuclear cores formed as a result of self-arrangement and their composition did not depend on the lanthanide ion. The complexes and sodium dimethyl N-benzoylamidophosphate have been characterized by single-crystal X-ray diffraction. The absorption spectra of the complexes were measured at 300 and 4 K. The dysprosium and ytterbium complexes exhibited weak emission in the visible and IR regions, respectively. Temperature dependences of magnetic susceptibility (χM) of the dysprosium, holmium, and erbium compounds were studied. It was found that χM vs T dependences were governed by the crystal field splitting effects with the Δ parameter being in the range 5-17 cm-1. Slow magnetic relaxation was found for the dysprosium complex by ac magnetic measurements, while no significant out-of-phase signals were detected for holmium and erbium complexes.

12.
Acta Crystallogr E Crystallogr Commun ; 75(Pt 7): 939-941, 2019 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-31391999

RESUMO

In the title compound, C20H18NO3P, the C=O and P=O groups of the carbacyl-amido-phosphate (CAPh) fragments are located in a synclinal position relative to each other and are pre-organized for bidentate chelate coordination of metal ions. The N-H group is involved in the formation of an intra-molecular hydrogen bond. In the crystal, mol-ecules do not form strong inter-molecular inter-actions but the mol-ecules are linked via weak C-H⋯π inter-actions, forming chains along [001].

13.
Acta Crystallogr E Crystallogr Commun ; 74(Pt 12): 1838-1841, 2018 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-30574384

RESUMO

The title compound, [Pd2(C2H8N2)2(CH2O6P2)]·4H2O, comprises of a binuclear mol-ecule (point group symmetry 2), with a twofold rotation axis running through the central C atom of the methyl-enedi-phospho-nate (MDP) anion. The PdII atom has a square-planar coordination environment defined by the N atoms of a bidentate ethyl-enedi-amine (en) ligand and two O atoms of the bridging MDP anion. In the crystal structure, metal complexes are arranged in layers parallel (001) and are sandwiched between layers containing disordered water mol-ecules of crystallization. Extensive intra-layer hydrogen bonds of the type N-H⋯O in the metal complex layer and O-H⋯O in the water layer, as well as O-H⋯O hydrogen bonds between the two types of layers, lead to the formation a three-dimensional network structure. The two lattice water mol-ecules are each equally disordered over two positions.

14.
Acta Crystallogr E Crystallogr Commun ; 73(Pt 7): 1076-1081, 2017 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-28775887

RESUMO

The asymmetric unit of [La(C20H21N3O3PS)3(C12H8N2)] is created by one LaIII ion, three deprotonated N-{bis-[meth-yl(phen-yl)amino]-phosphor-yl}benzene-sulfonamidate (L-) ligands and one 1,10-phenanthroline (Phen) mol-ecule. Each LaIII ion is eight-coordinated (6O+2N) by three phosphoryl O atoms, three sulfonyl O atoms of three L- ligands and two N atoms of the chelating Phen ligand, leading to the formation of six- and five-membered metallacycles, respectively. The lanthanum coordination polyhedron has a bicapped trigonal-prismatic geometry. 'Sandwich-like' intra-molecular π-π stacking inter-actions are observed between the 1,10-phenanthroline ligand and two benzene rings of two different L- ligands. The phenyl rings of L- that are not involved in the stacking inter-actions show minor positional disorder. Mol-ecules form layers parallel to the (010) plane due to weak C-H⋯O inter-molecular hydrogen bonds. Unidentified highly disordered solvate mol-ecules that occupy ca 400 Å3 large voids have been omitted from the refinement model.

15.
Chemphyschem ; 18(18): 2499-2508, 2017 Sep 20.
Artigo em Inglês | MEDLINE | ID: mdl-28763151

RESUMO

The use of DFT-calculated energy-vector diagrams (EVDs) featuring the topology of pairwise intermolecular interaction energies is applied to crystals of carbo-benzenes. A homogeneous set of six ideally centrosymmetric tetraphenyl-carbo-benzenes is selected, with various substituents R in para positions: R=4-anisyl, 1-ethyl-2-phenyl-1H-indol-3-yl, 2-chloro-2-(1-ethyl-2-phenyl-1H-indol-3-yl)ethenyl, tetradecyl, and 9,9-dihexyl-9H-fluoren-2-yl, 2-(9,9-dihexyl-9H-fluoren-2-yl)ethynyl. The basic structural motifs (BSMs) of the crystals vary from layers to columns, depending on the size and shape of the substituents R. The BSM cohesion is shown to rely on π-stacking, CH-π and dispersive interactions. Solvate molecules are shown to have a negligible role in the formation of the BSM, whereas they loosen the interaction between neighbouring BSMs.

16.
ACS Omega ; 2(12): 8911-8927, 2017 Dec 31.
Artigo em Inglês | MEDLINE | ID: mdl-31457419

RESUMO

We report here an efficient and easily reproducible two-step approach to heterocycle-substituted amino-pyrazoles from heterocyclic acetonitriles and their unprecedented subsequent transformations to fully substituted pyrazoles. Such transformations include regioselective derivatization from polyamino derivatives, formation of tetracyclic compounds in up to 45% overall yield, and deaminative transformations through diazotization, followed by arylation through Suzuki-Miyaura cross-coupling and C-H activation, providing arylated pyrazoles in up to 71% yield over four steps. This strategy allows the swift introduction of significant molecular complexity to a range of scaffolds.

17.
Acta Crystallogr E Crystallogr Commun ; 72(Pt 12): 1683-1686, 2016 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-27980809

RESUMO

In the mol-ecular structure of the title compound, [CaNa(C10H20Cl3N3O2P)3(H2O)], the Ca2+ ion has a slightly distorted octa-hedral coordination environment defined by six O atoms which belong to the carbonyl and phosphoryl groups of the three coordinating ligands. Two Cl atoms of CCl3 groups and four O atoms form the coordination environment of the Na+ ion: three from the carbonyl groups of ligands and one O atom from a coordinating water mol-ecule. In the crystal, the bimetallic complexes are assembled into chains along the c-axis direction via O-H⋯O hydrogen bonds that involve the coordinating water mol-ecules and the phosphoryl groups.

18.
Acta Crystallogr E Crystallogr Commun ; 72(Pt 2): 111-3, 2016 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-26958365

RESUMO

In the title compound, [U(C13H9N4O)(NO3)O2(H2O)]·CH3CN·H2O, the U(VI) atom is seven-coordinated in a distorted penta-gonal-bipyramidal N2O5 manner by one tridentate triazole ligand, one monodentate nitrate anion and one water mol-ecule in the equatorial plane and by two uran-yl(VI) O atoms in the axial positions. In the crystal, the U(VI) complex mol-ecule is linked to the water and aceto-nitrile solvent mol-ecules through N-H⋯N, O-H⋯O and O-H⋯N hydrogen bonds, forming a sheet structure parallel to the bc plane. The sheets are further linked by an additional O-H⋯O hydrogen bond, forming a three-dimensional network.

19.
Acta Crystallogr E Crystallogr Commun ; 71(Pt 9): 1077-80, 2015 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-26396853

RESUMO

The title compound, [CrCu(C5H11NO2)(C5H12NO2)(NCS)2(H2O)] or [Cr(µ-mdea)Cu(µ-Hmdea)(NCS)2H2O], (where mdeaH2 is N-methylethanolamine, C5H13NO2) is formed as a neutral heterometal Cu(II)/Cr(III) complex. The mol-ecular structure of the complex is based on a binuclear {CuCr(µ-O)2} core. The coordination environment of each metal atom involves the N,O,O atoms of the tridentate ligand, one bridging O atom of the ligand and the N atom of the thio-cyanato ligands. The Cu(II) ion adopts a distorted square-pyramidal coordination while the Cr(III) ion has a distorted octa-hedral coordination geometry completed by the aqua ligand. In the crystal, the binuclear complexes are linked via two pairs of O-H⋯O hydrogen bonds to form inversion dimers, which are arranged in columns parallel to the a axis. In the µ-mdea ligand two -CH2 groups and the methyl group were refined as disordered over two sets of sites with equal occupancies. The structure was refined as a two-component twin with a twin scale factor of 0.242 (1).

20.
Dalton Trans ; 44(35): 15508-22, 2015 Sep 21.
Artigo em Inglês | MEDLINE | ID: mdl-26239675

RESUMO

A series of complexes Ln(Pip)3(Phen) (Ln(iii) = La, Ce-Nd, Sm-Lu, Y; HPip (CAPh type ligand) = 2,2,2-trichloro-N-(dipiperidin-1-yl-phosphoryl)acetamide, Phen = 1,10-phenanthroline) has been synthesized. The lanthanum(iii) doped europium(iii) complexes ([LaxEu1-x(Pip)3(Phen)], x = 0.99, 0.95, 0.50) have been obtained by the co-crystallization method. The complexes have been characterized by means of X-ray diffraction, IR, (1)H and (31)P-NMR and absorption spectroscopy. Emission and excitation luminescence spectra were recorded at 295 and 77 K. The lifetime values (τ) for the emission of all europium complexes were determined. The (5)D0 luminescence quantum efficiency is 73-89%. The symmetries of the nearest europium surrounding in pure and doped complexes were evaluated from the Stark splitting of (5)D0-(7)FJ transitions. Crystal structures of [Ln(Pip)3(Phen)] (Ln = Nd (1), Eu (2) and Tb (3)) have been determined. Lattice parameters of the [Ln(Pip)3(Phen)] (Ln = Tb, Yb) and the doped [LaxEu1-x(Pip)3(Phen)] (x = 0.99, 0.95, 0.50) complexes have been measured. The presence of four polymorphs within a number of rare earth elements has been estimated: two in triclinic (Ln1 = La, Nd; Ln2 = Eu), one in the monoclinic (Ln3 = Tb) and one in the rhombic (Ln4 = Tb, Yb) symmetry. Complex 3 can be obtained in two crystal modifications: monoclinic and orthorhombic ones.

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