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Ricardo Baggio

Publications and source records attributed to Ricardo Baggio.

At least 37 records · Page 2Linked to original sources
PubMed2005

Bis{1-n-hexyl-3-methyl-4-[1-(phenylimino)propyl]-1H-pyrazol-5-olato}copper(II): a new copper(II) complex with a chelating alkylpyrazolone-based enamine.

The title compound, [Cu(C19H26N3O)2], is the first reported complex of the alkylpyrazolone-derived ligand 1-n-hexyl-3-methyl-4-[1-(phenylimino)propyl]-1H-pyrazol-5(4H)-one. The most notable feature is the imine-enol character presented by the ligand due to coordination, in spite of its enamine-ketone structure in the free state. The ligand chelates through N and O atoms, resulting in a square-planar coordination around the CuII atom, which lies on an inversion centre.

Journal Article↗
PubMed2005

Bis[(acetato-kappa(2)O,O')bis(4,4'-dimethyl-2,2'-bipyridyl-kappa(2)N,N')zinc(II)] trithionate pentahydrate.

The title ionic zinc-acetate complex, [Zn(C2H3O2)(C12H12N2)2]2(S3O6).5H2O, contains a ZnN4O2 nucleus provided by the three bidentate ligands acting in a chelating mode. The trithionate unit, in turn, acts as an isolated charge-balancing counter-ion. The structure has a three-dimensional assembly achieved through three different interaction types, viz. Coulomb, hydrogen bonding and pi-pi. The trithionate group and one of the solvent water molecules are disordered around inversion centers.

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PubMed2005

Two Cd and Hg peroxodisulfate complexes with aromatic amines.

The crystal structures of two complexes containing the peroxodisulfate anion are reported, namely mu-peroxodisulfato-1kappaO:2kappaO'-bis[(acetato-kappa2O,O')aqua(2,2':6',2''-terpyridine-kappa3N,N',N'')cadmium(II)] heptahydrate, [Cd2(C2H3O2)2(S2O8)(C15H11N2)2(H2O)2].7H2O, (I), and catena-poly[[[bis(2,2'-bipyridine-kappa2N,N')mercury(II)]-mu-peroxodisulfato-kappa2O:O'] 0.4-hydrate], {[Hg(C10H8N2)2(S2O8)].0.4H2O}n, (II). In both structures, the anion behaves as a bridge, linking neighbouring coordination polyhedra in two different ways, either tightly bound to the heptacoordinated Cd2+ cation forming neatly separated dimeric entities in (I) or across a shorter O-S-O path producing weakly connected chains by way of 'semicoordination' to the Hg2+ cations in (II).

Journal Article↗
PubMed2005

catena-Poly[copper(II)-mu-L-tyrosyl-L-leucinato].

In the title compound, [Cu(C15H20N2O4)]n, the copper(II) coordination is square planar. The anionic L-tyrosyl-L-leucinate ligand binds in an N,N',O-tridentate mode to one Cu(II) cation on one side and in an O-monodentate mode to a second Cu(II) cation on the other side, thus defining -Cu-O-C-O-Cu'- chains which run along the a axis. These chains are held together by a strong hydrogen bond involving the hydroxy H atom.

Catenanes↗
PubMed2004

Di-mu-sulfito-bis[(4,4'-dimethyl-2,2'-bipyridine)zinc(II)] dihydrate and poly[[aqua(1,10-phenanthroline)zinc(II)]-mu3-sulfito-zinc(II)-mu3-sulfito].

Two different zinc sulfite compounds have been prepared through the decomposition of pyrosulfite-dithionite ions in aqueous solution, viz. a dimeric complex, di-mu-sulfito-kappa3O,O':O'';kappa3O:O',O''-bis[(4,4'-dimethyl-2,2'-bipyridine-kappa2N,N')zinc(II)] dihydrate, [Zn2(SO3)2(C12H12N2)2].2H2O, (I), which was solved and refined from a twinned sample, and an extended polymer, poly[[aqua(1,10-phenanthroline-kappa2N,N')zinc(II)]-mu3-sulfito-kappa2O:O':O''-zinc(II)-mu3-sulfito-kappa3O:O:O'], [Zn2(SO3)2)(C12H10N2)(H2O)]n, (II). In (I), the dinuclear Zn(II) complex has a center of symmetry. The cation is five-coordinate in a square-pyramidal arrangement, the anion fulfilling a bridging chelating role. Compound (II) comprises two different zinc units, one being five-coordinate (square pyramidal) and the other four-coordinate (trigonal pyramidal), and two independent sulfite groups with different binding modes to the cationic centers.

Journal Article↗
PubMed2004

4,4'-Bis(N,N-diethylamino)-2,2'-bipyridine.

The title compound, C(18)H(26)N(4), contains two almost identical independent molecules that lie about inversion centres. Each molecule has a planar bipyridine nucleus and two terminal diethylamine groups oriented at almost right angles to the core. These diethylamine branches act as spacers, producing a very open structure with one of the lowest densities reported among related compounds. The most important intermolecular interactions are of the C-H...pi type, which connect non-equivalent moieties.

Journal Article↗
PubMed2004

Isolation and characterization of a polymeric lanthanum citrate.

The first lanthanide citrate coordination polymer with the formula [La(Hcit)(H(2)O)](n) (Hcit(3-) = C(OH)(COO(-))(CH(2)COO(-))(2)) was prepared from La(2)O(3) and citric acid at pH = 2.2-2.5 under hydrothermal conditions at 120 degrees C. The compound was characterized by elemental analysis, IR, TG-DTA, and X-ray crystallography. It is thermally stable up to 158 degrees C and insoluble in common solvents. The compound crystallizes in the monoclinic space group C2/c with a = 16.765(3) A, b = 8.822(2) A, c = 14.048(3) A, beta = 120.64(3) degrees , and Z = 8. The structure consists of chains of La(III) cations bridged by O--C--O groups with pendant Hcit anions forming a pillar structure. The Hcit ligand is involved in six La--O bonds to five different La centers in a very compact 3D structure.

Journal Article↗
PubMed2004

Two enamines derived from 1-n-alkyl-3-methylpyrazol-5-ones.

The first two crystal structures of enamines derived from 1-n-alkyl-3-methyl-5-pyrazolones, namely 1-(n-hexyl)-3-methyl-4-[1-(phenylamino)propylidene]-2-pyrazolin-5-one, C19H27N3O, (I), and N,N'-bis[1-[1-(n-hexyl)-3-methyl-5-oxo-2-pyrazolin-4-ylidene]ethyl]hexane-1,6-diamine, C30H52N6O2, (II), are reported. The molecule of (II) lies about an inversion centre. Both (I) and (II) are stabilized by intramolecular N-H...O hydrogen bonding. This confirms previous results based on spectroscopic evidence alone.

Journal Article↗
PubMed2004

Tetraaqua(3,4,7,8-tetramethyl-1,10-phenanthroline-kappa2N,N')zinc(II) thiosulfate.

In the title complex of zinc(II) with 3,4,7,8-tetramethyl-1,10-phenanthroline (tmph), viz. [Zn(C16H16N2)(H2O)4](S2O3), the metal atom has a monomeric octahedral ZnN2O4 complex environment comprising two N-atom donors from the tmph group and four aqua O-atom donors. The complex cation is connected to four thiosulfate anions through a compact hydrogen-bonding network involving all coordinated aqua H-atom donors and all the outer acceptors (O and S) of the anion.

Anti-Inflammatory Agents, Non-Steroidal↗
PubMed2004

Dinuclear asymmetric ruthenium complexes with 5-cyano-1,10-phenanthroline as a bridging ligand.

New dinuclear asymmetric ruthenium complexes of the type [(bpy)(2)Ru(5-CNphen)Ru(NH(3))(5)](4+/5+) (bpy = 2,2'-bipyridine; 5-CNphen = 5-cyano-1,10-phenanthroline) have been synthesized and characterized by spectroscopic, electrochemical, and photophysical techniques. The structure of the cation [(bpy)(2)Ru(5-CNphen)Ru(NH(3))(5)](4+) has been determined by X-ray diffraction. The mononuclear precursor [Ru(bpy)(2)(5-CNphen)](2+) has also been prepared and studied; while its properties as a photosensitizer are similar to those of [Ru(bpy)(3)](2+), its luminescence at room temperature is quenched by a factor of 5 in the mixed-valent species [(bpy)(2)Ru(II)(5-CNphen)Ru(III)(NH(3))(5)](5+), pointing to the occurrence of intramolecular electron-transfer processes that follow light excitation. From spectral data for the metal-to-metal charge-transfer transition Ru(II) --> Ru(III) in this latter complex, a slight electronic interaction (H(AB) = 190 cm(-1)) is disclosed between both metallic centers through the bridging 5-CNphen.

Journal Article↗
PubMed2004

A novel five-coordinate cadmium phenanthroline thiosulfate.

The structure of the novel cadmium phenanthroline thiosulfate poly[[(1,10-phenanthroline-kappa(2)N,N')cadmium(II)]-micro(3)-thiosulfato-kappa(3)S:S:O], [Cd(S(2)O(3))(C(12)H(8)N(2))](n), with a pentacoordinated Cd centre, is reported. It forms linear chains built up around a 2(1) axis and is isostructural with the known bipyridine homologue. The structure is also compared with a previously reported closely related monoaqua monohydrated phase, where the Cd(2+) cation is hexacoordinated. The incidence of weak C-H.O interactions in the determination of its general packing properties is discussed.

Journal Article↗
PubMed2004

Catena-poly[[bis(hexafluoroacetylacetonato-kappa2O,O')zinc(II)]-micro-4,4'-bipyridine-kappa2N:N'].

The structure of the title compound, catena-poly[[bis(1,1,1,5,5,5-hexafluoropentane-2,4-dionato-kappa(2)O,O')zinc(III)]-micro-4,4'-bipyridine-kappa(2)N:N'], [Zn(C(5)HF(6)O(2))(2)(C(10)H(8)N(2))](n), consists of polymeric chains, running in two perpendicular directions, organized as planes normal to the tetragonal axis. The elemental unit of the chains is the zinc(II) coordination polyhedron bisected by a twofold symmetry axis, and thus only half of the unit is independent. The octahedral coordination geometry of the metal centre is composed of two oxygen-chelating (symmetry-related) hexafluoroacetylacetonate groups and two translationally related 4,4'-bipyridine groups, which act as connecting agents in the polymer structure. The stabilization of this architecture of chains and planes is associated with a number of weak C-H.O and C-H.F hydrogen bonds.

Journal Article↗
PubMed2003

Three yttrium crotonate complexes with diimines.

The synthesis and crystal structures of three new yttrium crotonate (crot) compounds, associated with three different nitrogenous bases, namely 1,10-phenanthroline (phen), 4-methyl-1,10-phenanthroline (mphen) and 2,2'-bipyridylamine (bpa), are presented. All three compounds organize as centrosymmetric dimers, to give tetra-micro-crotonato-bis[crotonato(1,10-phenanthroline)yttrium(III)] dihydrate, [Y(2)(C(4)H(5)O(2))(6)(C(12)H(8)N(2))(2)].2H(2)O or [Y(crot)(3)(phen)](2).2H(2)O, (I), tetra-micro-crotonato-bis[crotonato(4-methyl-1,10-phenanthroline)yttrium(III)] dihydrate, [Y(2)(C(4)H(5)O(2))(6)(C(13)H(10)N(2))(2)].2H(2)O or [Y(crot)(3)(mphen)](2).2H(2)O, (II), and tetra-micro-crotonato-bis[diaqua(crotonato)yttrium(III)] 2,2'-bipyridylamine tetrasolvate, [Y(2)(C(4)H(5)O(2))(6)(H(2)O)(4)].4C(10)H(9)N(3) or [Y(crot)(3)(aq)(2)](2).4(bpa), (III). Complexes (I) and (II) are isomorphous, with the bases acting as chelating ligands. In complex (III), the coordination sphere is built up of carboxylate and aqua ligands, with the non-coordinated diimine acting as included solvent.

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