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E Gutiérrez-Puebla

Publications and source records attributed to E Gutiérrez-Puebla.

8 recordsLinked to original sources
PubMed2002

In(2)(OH)(3)(BDC)(1.5) (BDC = 1,4-benzendicarboxylate): an In(III) supramolecular 3D framework with catalytic activity.

The new hybrid inorganic-organic polymer In(2)(OH)(3)[O(4)C(8)H(4)](1.5) has been hydrothermally obtained. Conditions for the synthesis are reported. The crystal structure of this material has been established by single-crystal X-ray diffraction: it is monoclinic, with space group P2(1)/c (Nomicron. 14), a = 6.772(1) A, b = 10.329(2) A, c = 20.152(3) A, beta = 97.573(3) degrees. The In atoms are octahedrally coordinated by three hydroxide groups and three different molecules of carboxylate ligand. The resulting polymeric 3D structure can be envisaged as having been generated from a honeycomb (6,3) 2D that is cross-linked by the BDC organic anions. Data of IR and TGA-DTA studies, as well as the results of reduction of nitroaromatics and selective oxidation of organic sulfide reactions catalyzed by the new material, are reported.

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PubMed2001

Step-by-step uncoordination of the pyrazolyl rings of hydrotris(pyrazolyl)borate ligands in comlexes of Rh and RhIII.

Compounds of rhodium(I) and rhodium(III) that contain ancillary hydrotris(pyrazolyl)borate ligands (Tp') react with monodentate and bidentate tertiary phosphanes in a step-wise manner, with incorporation of P-donor atoms and concomitant replacement of the Tp' pyrazolyl rings. Accordingly, [Rh(kappa3-TpMe2)(C2H4)(PMe3)] (1b), converts initially into [Rh(kappa2-TpMe2)-(PMe3)2] (3), and then into [Rh(kappa1-TpMe2)-(PMe3)3] (2) upon interaction with PMe3 at room temperature, in a process which can be readily reversed under appropriate experimental conditions. Full disengagement of the Tp' ligand is feasible to give Tp' salts of rhodium(I) complex cations, for example, [Rh(CO)(dppp)2]-[TpMe2,4-Cl] (5; dppp = Ph2P(CH2)3PPh2), or [Rh(dppp)2][TpMe2,4-Cl] (6). Bis(hydride) derivatives of rhodium(III) exhibit similar substitution chemistry, for instance, the neutral complex [Rh(Tp)-(H)2(PMe3)] reacts at 20 degrees C with an excess of PMe3 to give [Rh(H)2-(PMe3)4][Tp] (9b). Single-crystal X-ray studies of 9b, conducted at 143 K, demonstrate the absence of bonding interactions between the [Rh(H)2(PMe3)4]+ and Tp ions, the closest Rh...N contact being at 4.627 A.

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PubMed2001

New chiral molecular tweezers with a bis-Tröger's base skeleton.

A convenient synthesis of 5alpha,8alpha,14alpha,17alpha-5,17:8,14-dimethano-5,8,14,17-tetraaza-5,6,7,8,13,14,17,18-octahydrodibenzo[e,e']benzo[1,2-a:3,4-a']dicyclooctene derivatives is described, and the compounds have been fully characterized by NMR; in some cases, the molecular structure has been determined by X-ray crystallography. These compounds represent the first examples of a new class of molecular tweezers.

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PubMed2000

Denticity Changes of Hydrotris(pyrazolyl)borate Ligands in Rh(I) and Rh(III) Compounds: From kappa(3)- to Ionic "kappa(0)"-Tp'

Isolated hydrotris(pyrazolyl)borate anions Tp' were obtained as salts of metal complex cations (see picture) by the displacement of Rh-coordinated kappa(3)-N,N',N"-Tp' by PMe(3) (Tp'=Tp and Tp(Me2)). With [(kappa(3)-Tp(Me2))Rh(C(2)H(4))(2)], stepwise diplacement of the Tp(Me2) ligand allowed the isolation of complexes exhibiting the kappa(2)- Tp(Me2) and kappa(1)-Tp(Me2) coordination modes.

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PubMed1999

A Germanium Zeotype Containing Intratunnel Transition Metal Complexes.

A new zeolite-type structure is adopted by (NH(4))(+)[M(NH(3))(2)](+)(Ge(9)O(19))(2-) (M=Cu, Ag; shown in the picture). These compounds are the first microporous germanates containing a transition metal complex inside their tunnels. The large separation between the metal centers and the unhindered access of reactants to these active sites through uniformly sized channels make these materials a good point of departure for designing new catalysts.

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