Coordination geometry flexibility driving supramolecular isomerism of Cu/Mo pillared-layer hybrid networks.

Hydrothermal synthesis led to four novel 3D pillared-layer metal-organic frameworks: [Cu(4,4'-bipy)(MoO)·0.3HO] (1), [Cu(4,4'-bipy)(MoO)·0.25HO] (2), [Cu(4,4'-bipy)(MoO)·0.

Multivalent hydrogen-bonded architectures directed by self-complementarity between [Cu(2,2'-biimidazole)] and malonate building blocks.

The synthesis and structural characterization of four novel supramolecular hydrogen-bonded arrangements based on self-assembly from molecular `[Cu(2,2'-biimidazole)]' modules and malonate anions are presented, namely, tetrakis(2,2'-biimidazole)di-μ-chlorido-dimalonatotricopper(II) pentahydrate, [Cu(CHO)Cl(CHN)]·5HO or [Cu(Hbiim)(μ-Cl)Cu(mal)]·5HO, aqua(2,2'-biimidazole)malonatocopper(II) dihydrate, [Cu(CHO)(CHN)(HO)]·2HO or [Cu(Hbiim)(mal)(HO)]·2HO, bis[aquabis(2,2'-biimidazole)copper(II)] dimalonatodiperchloratocopper(II) 2.2-hydrate, [Cu(CHN)(HO)][Cu(CHO)(ClO)]·2.2HO or [Cu(Hbiim)(HO)][Cu(mal)(ClO)]·2.

Chemistry of transition-metal complexes containing functionalized phosphines: synthesis and structural analysis of rhodium(I) complexes containing allyl and cyanoalkylphosphines.

A series of related acetylacetonate-carbonyl-rhodium compounds substituted by functionalized phosphines has been prepared in good to excellent yields by the reaction of [Rh(acac)(CO)] (acac is acetylacetonate) with the corresponding allyl-, cyanomethyl- or cyanoethyl-substituted phosphines. All compounds were fully characterized by P, H, C NMR and IR spectroscopy. The X-ray structures of (acetylacetonato-κO,O')(tert-butylphosphanedicarbonitrile-κP)carbonylrhodium(I), [Rh(CHO)(CO)(CHN)] or [Rh(acac)(CO)(BuP(CHCN)}] (2b), (acetylacetonato-κO,O')carbonyl[3-(diphenylphosphanyl)propanenitrile-κP]rhodium(I), [Rh(CHO)(CHN)(CO)] or [Rh(acac)(CO){PhP(CHCHCN)}] (2h), and (acetylacetonato-κO,O')carbonyl[3-(di-tert-butylphosphanyl)propanenitrile-κP]rhodium(I), [Rh(CHO)(CHN)(CO)] or [Rh(acac)(CO){BuP(CHCHCN)}] (2i), showed a square-planar geometry around the Rh atom with a significant trans influence over the acetylacetonate moiety, evidenced by long Rh-O bond lengths as expected for poor π-acceptor phosphines.

Novel MoO2/carbon hierarchical nano/microcomposites: synthesis, characterization, solid state transformations and thiophene HDS activity.

Novel MoO(2)/C nano/microcomposites were prepared via a bottom-up approach by hydrothermal carbonization of a solution of glucose as a carbon precursor in the presence of polyoxometalates (POMs: phosphomolybdic acid [H(3)PMo(12)O(40)] and ammonium heptamolybdate tetrahydrate [(NH(4))(6)Mo(7)O(24)]·4H(2)O). The structural characterization by FT-IR, XRPD, SEM and TEM analyses revealed the controlled formation of hierarchical MoO(2)/C composites with different morphologies: strawberry-like, based on carbon microspheres decorated with MoO(2) nanoparticles; MoO(2)/C core-shell composites; and irregular aggregates in combination with ring-like microstructures bearing amorphous Mo species. These composites can be fine-tuned by varying reaction time, glucose/POM ratio and type of POM precursor.

A non-photochemical route for the regioselective preparation of rtct-pyridylcyclobutanes via hydrothermal isomerisation promoted by polymolybdates.

A novel approach for the regioselective preparation of rtct-tpcb (tpcb = tetrapyridylcyclobutanes) compounds promoted by polymolybdates under hydrothermal conditions is reported; these isomers are stabilised as counterions in inorganic-organic hybrid solids and are obtained in high to fair yield.

Hydrogen-bonded networks in trans-3-(3-pyridyl)acrylic acid and rctt-3,3'-(3,4-dicarboxycyclobutane-1,2-diyl)dipyridinium dichloride.

The structure of trans-3-(3-pyridyl)acrylic acid, C(8)H(7)NO(2), (I), possesses a two-dimensional hydrogen-bonded array of supramolecular ribbons assembled via heterodimeric synthons between the pyridine and carboxyl groups. This compound is photoreactive in the solid state as a result of close contacts between the double bonds of neighbouring molecules [3.821 (1) A] along the a axis.

4,6-Dimethyl-2-(3-pyridyl)quinolin-5-amine.

The title compound, C(16)H(15)N(3), shows a hindrance effect between adjacent amino and methyl groups that leads to a structural distortion, which is reflected in the non-planarity of the quinoline entity and in the bond angles and distances. The crystal packing consists of chains along the b axis sustained by an intermolecular hydrogen bond between the amino group and the N atom of the pyridyl ring.

2,6-Bis[1-(2-isopropyl-phenyl-imino)-ethyl]-pyridine.

The title compound, C(27)H(31)N(3), has E substitution at each imine double bond where the two N atoms adopt a trans-trans relationship. The benzene rings are twisted out of the mean plane of the pyridine ring; the mean planes of the aromatic groups are rotated by 63.0 (1) and 72.

Supramolecular isomerism in multivalent metal-templated assemblies with topochemical influence in the regioselective synthesis of tetrakis(2-pyridyl)cyclobutane isomers.

An unprecedented example of supramolecular isomerism based on 2D hydrogen-bonded multi-component networks that leads to the preparation of different photoproducts via a topochemical transformation is reported.

A mesoporous hydrogen-bonded organic-inorganic framework bearing the isopolymolybdate [Mo36O112(OH2)16]8-.

The mesoporous H-bonded organic-inorganic hybrid material is built up from the assembly of the isopolymolybdate [Mo36O112(OH2)16]8- and H2bipy2+, which displays large interconnected cavities and exhibits a reversible water sorption behaviour while maintaining its striking crystal integrity.

Synthesis and reactivity of iridium complexes with pyridine and piperidine ligands: models for hydrodenitrogenation.

The complexes [Ir(H)2(eta1-N-L)2(PPh3)2]PF6, L = py (1), iQ (2) and pip (3) (py = pyridine, iQ = isoquinoline, pip = piperidine) have been synthesized in high yields by hydrogenation of [Ir(cod)(PPh3)2]PF6 in the presence of the appropriate nitrogen compound. When hydrogen is bubbled through 1,2-dichloroethane solutions of 1 or 2, two new species were formed in each case by C-Cl bond activation of the solvent, Ir(H)2Cl(eta1-N-L)(PPh3)2 (L = py, 4; iQ, 5) and IrH(Cl)2(eta1-N-L)(PPh3)2 (L = py, 6; iQ, 7). Reaction of 3 with py or iQ yielded complexes 1 and 2, respectively, while under a slow stream of carbon monoxide the complex [Ir(H)2(eta1-N-pip)(CO)(PPh3)2]PF6 (8) was produced.

Robust hydrogen-bonded self-assemblies from biimidazole complexes. Synthesis and structural characterization of [M(biimidazole)2(OH2)2]2+ (M = Co2+, Ni2+) complexes and carboxylate modules.

A robust heteromeric hydrogen-bonded synthon [R2(2) (9)-Id] is exploited to drive the modular self-assembly of four coordination complexes [M(H2biim)2(OH2)2]2+ (M = Co2+, Ni2+) and carboxylate counterions. This strategy allowed us to build molecular architectures of 0-, 1-, and 2-dimensions. A hydrogen-bonded 2D-network with cavities has been designed, which maintains its striking integrity after reversible water desorption-resorption processes.

C-C bond-forming reactions of Ir(III)-alkenyls and nitriles or aldehydes: generation of reactive hydride- and alkyl-alkylidene compounds and observation of a reversible 1, 2-H shift in stable hydride-Ir(III) alkylidene complexes.

Nucleophilic attack of the beta-carbon of an Ir(III)-alkenyl functionality onto the alpha-carbon of a coordinated nitrile- or aldehyde occurs intramoleculary to yield initially iridacyclic structures. Nitriles give rise to isolable complexes that contain delocalized five-membered rings (iridapyrroles, e.g.

Synthesis and Characterization of Heterodinuclear IrCo, RuCo, IrNi, and RuNi Complexes Containing Pyrazolate and Pyrazolylborate Ligands.

Treatment of the metallo ligands [ML(pz)(2)(Hpz)] (pz = pyrazolate; L = C(5)Me(5), M = Ir (1); L = mesitylene, M = Ru (3)) with [M'Cl{HB(3-i-Pr-4-Br-pz)(3)}] (M' = Co (4), Ni (5)) yields heterodinuclear complexes of formula [LM(&mgr;-pz)(2)(&mgr;-Cl)M'{HB(3-i-Pr-4-Br-pz)(3)}] (L = C(5)Me(5); M = Ir; M' = Co (6), Ni (7). L = mesitylene; M = Ru; M' = Co (8)). The related complex [Ru(eta(6)-p-cymene)(pz)(2)(Hpz)] (2) reacts with equimolar amounts of 4 or 5 to give mixtures of the corresponding bis(&mgr;-pyrazolato) &mgr;-chloro complexes [(eta(6)-p-cymene)Ru(&mgr;-pz)(2)(&mgr;-Cl)M'{HB(3-i-Pr-4-Br-pz)(3)}] (M' = Co (9), Ni (10)) and the triply pyrazolato-bridged complexes [(eta(6)-p-cymene)Ru(&mgr;-pz)(3)M'{HB(3-i-Pr-4-Br-pz)(3)}] (M' = Co (11), Ni (12)).