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1.
Inorg Chem ; 55(13): 6504-10, 2016 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-27308962

RESUMO

A novel small-molecule compound of lithium iodine and 3-hydroxypropionitrile (HPN) has been successfully synthesized. Our combined experimental and theoretical studies indicated that LiIHPN is a Li-ion conductor, which is utterly different from the I(-)-anion conductor of LiI(HPN)2 reported previously. Solid-state lithium-air batteries based on LiIHPN as the electrolyte exhibit a reversible discharge capacity of more than 2100 mAh g(-1) with a cyclic performance over 10 cycles. Our findings provide a new way to design solid-state electrolytes toward high-performance lithium-air batteries.

2.
J Am Chem Soc ; 137(49): 15350-3, 2015 Dec 16.
Artigo em Inglês | MEDLINE | ID: mdl-26595532

RESUMO

Controlling the dopant type, number, and position in doped metal nanoclusters (nanoparticles) is crucial but challenging. In the work described herein, we successfully achieved the mono-cadmium doping of Au25 nanoclusters, and revealed using X-ray crystallography in combination with theoretical calculations that one of the inner-shell gold atoms of Au25 was replaced by a Cd atom. The doping mode is distinctly different from that of mono-mercury doping, where one of the outer-shell Au atoms was replaced by a Hg atom. Au24Cd is readily transformed to Au24Hg, while the reverse (transformation from Au24Hg to Au24Cd) is forbidden under the investigated conditions.

3.
J Am Chem Soc ; 136(44): 15521-4, 2014 Nov 05.
Artigo em Inglês | MEDLINE | ID: mdl-25329984

RESUMO

Two types of unprecedented Cp*Rh-based (Cp* = η(5)-C5Me5) complexes, two octadecanuclear macrocycles, and a nonanuclear bowl-shaped complex have been synthesized from two analogous pyridyl-functionalized imidazole-4,5-dicarboxylate ligands, 2-(pyridin-4-yl)-1H-imidazole-4,5-dicarboxylate ligand and 2-(pyridin-3-yl)-1H-imidazole-4,5-dicarboxylate ligand, respectively.

4.
J Am Chem Soc ; 136(41): 14608-15, 2014 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-25215429

RESUMO

Although reversible covalent activation of molecular hydrogen (H2) by transition-metal complexes is a common reaction, H2-mediated sophisticated reversible arrangements of organometallic frameworks have not yet been described. Herein, we report unusual organometallic transformations in solution that can be accomplished by uptake or release of H2. An efficient route for synthesizing air- and moisture-stable 16-electron M2L2-type metallacycles under very mild conditions has been developed. The new organometallic metallacycles favor the binding of small ligands such as MeCN, Cl(-), CO, and pyridine. The reaction of a coordinatively unsaturated 16-electron M2L2-type macrocyclic complex featuring thione ligands with 1 atm of H2 leads to the isolation of a 18-electron M2L3-type cylinder, along with hydride species. Remarkably, the obtained mixture underwent loss of H2 in a facile manner upon heating to re-form the starting M2L2-type complex. A possible mechanism is proposed for the reversible transformations.

5.
J Org Chem ; 75(14): 4796-805, 2010 Jul 16.
Artigo em Inglês | MEDLINE | ID: mdl-20568786

RESUMO

The monomer 1 derived from achiral 1-(aminoxy)cyclopropanecarboxylic acid (OAcc) and oligopeptides 2-9 consisting of a chiral alpha-aminoxy acid and an achiral alpha-aminoxy acid such as OAcc were synthesized and their structures characterized. The eight-membered-ring intramolecular hydrogen bond, namely the alpha N-O turn, was formed between adjacent residues independent of their chirality. However, the helix formation was sequence-dependent. Dipeptide 2 bearing chiral alpha-aminoxy acid (d-OAA) at the N-terminus and achiral OAcc at the C-terminus preferentially adopted a right-handed 1.8(8) helical structure, but dipeptide 3 (OAcc-d-OAA) did not. Theoretical calculation results, in good agreement with experimental ones, revealed that the biased handedness of alpha N-O turn found in OAcc residue depends on its preceding chiral residue. It was then found that the helical conformation was destroyed in the case of oligopeptides 6 and 7 [OAA-(OAcc)(n), n = 2, 3]. The crystal structure of tripeptide 8 ((i)PrCO-d-OVal-OAcc-d-OVal-NH(i)Bu) further disclosed the helical structure formed by three consecutive homochiral alpha N-O turns. This study has uncovered achiral aminoxy acid residues such as the OAcc unit as a useful building block to be incorporated into chiral aminoxy peptides to mimic chiral helix structure.


Assuntos
Aminoácidos/química , Ciclopropanos/química , Dipeptídeos/química , Nitrogênio/química , Oligopeptídeos/síntese química , Oxigênio/química , Dicroísmo Circular , Cristalografia por Raios X , Ciclopropanos/síntese química , Modelos Moleculares , Conformação Molecular , Dados de Sequência Molecular , Estrutura Molecular , Ressonância Magnética Nuclear Biomolecular , Oligopeptídeos/química
6.
Acta Crystallogr C ; 66(Pt 4): m97-100, 2010 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-20354296

RESUMO

In the title one-dimensional coordination polymer, {[Mn(C(5)O(5))(C(10)H(8)N(2))(H(2)O)].H(2)O}(n), each Mn(II) ion is seven-coordinated by four O atoms from two croconate ligands, two N atoms from a 2,2'-bipyridine (2,2'-bipy) ligand and one O atom from an aqua ligand. The croconate ligand bridges the Mn(II) ions in a bis-bidentate chelation mode, forming an extended [Mn(C(5)O(5))](n) chain running parallel to the [001] direction, with the lipophilic 2,2'-bipy ligands lying along one side and the hydrophilic water molecules along the opposite side. Coordinated water and solvent water molecules are arranged in the hydrophilic layer, which is characterized by O-H...O hydrogen bonds between croconate ligands. Meanwhile, 2,2'-bipy ligands from adjacent chains partially overlap and exhibit pi-pi interactions to form a lipophilic layer. The hydrophilic and lipophilic layers are arranged alternately to build a layer structure.


Assuntos
Manganês/química , Compostos Organometálicos/química , Polímeros/química , Cristalografia por Raios X , Ligação de Hidrogênio , Ligantes , Estrutura Molecular
7.
Chem Commun (Camb) ; (3): 350-2, 2008 Jan 21.
Artigo em Inglês | MEDLINE | ID: mdl-18399204

RESUMO

Octanuclear complexes with half-sandwich Ir, Rh and Ru fragments and tetra(4-pyridyl)porphyrin (L1) and oxalate (L2) spacer ligands [(Cp*M)4L1]2[L2]4 (M = Ir (6a) M = Rh (6b)), [((cymene)Ru)4(L1)]2[L2]4 were prepared and characterized.

9.
Chem Commun (Camb) ; (2): 162-4, 2006 Jan 14.
Artigo em Inglês | MEDLINE | ID: mdl-16372092

RESUMO

The assembly of soluble, air-stable, supramolecular structures {(Zn-TPyP)[Cp*Ir{S2C2(B10H10)}]4(THF)2}(2), {(Cu-TPyP)[Cp*Ir{S2C2(B10H10)}]4(THF)2}(3) and {(Zn-TPyP)[Cp*Ir{S2C2(B10H10)}]2.6(CHCl3)}n (4), based on metal-containing moieties [Cp*Ir{S2C2(B10H10)}] (1) bridged by nitrogen-based organic spacers, are described.


Assuntos
Compostos de Boro/química , Compostos Organometálicos/química , Compostos Organometálicos/síntese química , Porfirinas/química , Cristalografia por Raios X , Ligantes , Modelos Moleculares
10.
Chem Commun (Camb) ; (13): 1542-3, 2004 Jul 07.
Artigo em Inglês | MEDLINE | ID: mdl-15216371

RESUMO

The synthesis and crystal structure of the first mixed-metal organometallic polymer network containing phenylthiolato ligands, [K2Fe(SPh)4]n, are investigated. The simple phenylthiolate acts as a sigma- and pi-donor ligand to give a 3-D potassium iron coordination polymer with both metal-carbon and metal-sulfur coordination interactions.

11.
Dalton Trans ; 41(38): 11657-62, 2012 Oct 14.
Artigo em Inglês | MEDLINE | ID: mdl-22854827

RESUMO

Reported here are the bottom-up synthesis and structural analysis as well as the adsorption property investigation of a series of isostructural metal-organic frameworks based on carborane backbones and Cu(2)(CO(2))(4) units. All these compounds are 2D grid structures composed of four component rings. Using linear p-CDC (p-CDCH(2) = 1,12-dihydroxycarbonyl-1,12-dicarba-closo-dodecaborane) as a backbone, only one type of ring formed. However, five types of rings may exist when m-CDCH(2) (m-CDCH(2) = 1,7-dihydroxycarbonyl-1,7-dicarba-closo-dodecaborane) was used due to its varied orientation. Here, the solvent molecules play a key role in the formation of these compounds and the expected five types of rings were obtained. The gas sorption properties of compounds 5' and 8' were studied. These frameworks preferentially adsorb CO(2) over both CH(4) and N(2) due to the coordinatively unsaturated copper ions.

12.
Chem Commun (Camb) ; 48(37): 4435-7, 2012 May 11.
Artigo em Inglês | MEDLINE | ID: mdl-22456470

RESUMO

Organometallic rectangle 1 which undergoes [2+2] cycloaddition upon irradiation with sunlight and organometallic prism 3 which displayed interesting host-guest property were self-assembled based on a versatile building block.

13.
Chem Commun (Camb) ; 47(25): 7197-9, 2011 Jul 07.
Artigo em Inglês | MEDLINE | ID: mdl-21625720

RESUMO

A three-dimensional (3D) metal-organic framework {[Zn(2)(HBDC)(2)(dmtrz)(2)]·guest}(n) with pcu net has been solvothermally synthesized, which shows selective adsorption of linear and monobranched hexane isomers over a dibranched one.


Assuntos
Ácidos Dicarboxílicos/química , Hexanos/química , Compostos Organometálicos/química , Triazóis/química , Zinco/química , Adsorção , Isomerismo , Ligantes , Modelos Moleculares , Conformação Molecular
14.
Org Lett ; 13(7): 1864-7, 2011 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-21391556

RESUMO

Two novel sesterterpenoids, leucosceptroids C (1) and D (2), possessing unusual antipodal cyclopentenones while maintaining the stereochemistry and functionality of the tricyclic cores, were discovered from the leaves of Leucosceptrum canum (Labiatae). Their structures including absolute stereochemistries were determined by comprehensive NMR, MS, and single-crystal X-ray diffraction analyses. The potent antifeedant activity of 1 against the generalist plant-feeding insect Helicoverpa armigera (EC(50) = 0.017 µmol/cm(2)) suggested them to be new defensive sesterterpenoids of L. canum.


Assuntos
Ciclopentanos/química , Lamiaceae/química , Sesterterpenos/química , Animais , Ciclização , Ciclopentanos/farmacologia , Lepidópteros/efeitos dos fármacos , Modelos Moleculares , Estrutura Molecular , Folhas de Planta/química , Sesterterpenos/farmacologia , Estereoisomerismo
15.
Chem Commun (Camb) ; 46(20): 3556-8, 2010 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-20386861

RESUMO

Versatile and efficient procedures for the construction and modification of organometallic macrocycles with half-sandwich Ir corners via C-H activation and self-assembly have been developed.


Assuntos
Irídio/química , Compostos Macrocíclicos/síntese química , Compostos Organometálicos/síntese química , Cristalografia por Raios X , Compostos Macrocíclicos/química , Modelos Moleculares , Estrutura Molecular , Compostos Organometálicos/química , Estereoisomerismo
16.
Dalton Trans ; 39(44): 10712-8, 2010 Nov 28.
Artigo em Inglês | MEDLINE | ID: mdl-20941428

RESUMO

To systematically explore the assembly mechanism of a rutile-type open framework of {[Zn(3)(pbdc)(2)]·2H(3)O}(n) (3) (H(4)pbdc = 5-phosphonobenzene-1,3-dicarboxylic acid) constructed by 3-connected pbdc ligands and 6-connected Zn(3)(CO(2))(4)(PO(3))(2) secondary building units (Zn(3)-SBUs), three major factors including solvothermal procedures, types of solvents and amines, are taken into consideration. Seven novel structures, namely {[Zn(5)(pbdc)(2)(OH)(2)(H(2)O)(4)]·4H(2)O}(n) (1), {[Zn(3)(pbdc)(2)·H(2)O]·(Htea)·H(3)O·2-5(H(2)O)}(n) (2), {[Zn(3)(pbdc)(2)](H(3)O)(2)(dma)}(n) (4), {[Zn(2)(pbdc)(taea)]·3H(2)O}(n) (5), {[Zn(3)(pbdc)(2)(Hpda)(2)]·2H(2)O}(n) (6), {[Zn(5)(pbdc)(2)(Hpbdc)(2)]·2H(2)pz·9H(2)O}(n) (7), {[Zn(3)(pbdc)(2)]·Hpd·H(3)O·4H(2)O}(n) (8) are obtained. The results indicate that the layered-solvothermal method and the isopropanol solvent play crucial roles in the construction of the special anionic open framework of [Zn(3)(pbdc)(2)](2-). Changing these two factors led molecular assembly away from the rutile-type open framework. However, amines play a variable role in the framework, which means that by using appropriate amines, molecular assembly could generate the open framework of [Zn(3)(pbdc)(2)](2-) with pores decorated by amines. These results suggest a different approach towards decorating pores in anionic frameworks with precise structural information.

17.
Chem Commun (Camb) ; 46(7): 1100-2, 2010 Feb 21.
Artigo em Inglês | MEDLINE | ID: mdl-20126726

RESUMO

The layered-solvothermal synthesis of zinc acetate dihydrate with 5-phosphonobenzene-1,3-dicarboxylic acid yields a three-dimensional rutile-type porous metal-organic framework, which is an anionic open-framework containing local proton transfer with hydrated protons and showing excellent size-selective properties.

19.
Chemistry ; 13(1): 188-95, 2007.
Artigo em Inglês | MEDLINE | ID: mdl-17042047

RESUMO

The synthesis of half-sandwich transition metal complexes containing both 1,2-dichalcogenolato-1,2-dicarba-closo-docecaborane (Cab(E,E)) [Cab(E,E)=E(2)C(2)(B(10)H(10)); E = S, Se] and N-heterocyclic carbene (NHC) ligands is described. Addition of mono-NHC ligand to the 16e half-sandwich dichalcogenolato carborane complexes [Cp*Rh(Cab(E,E))], [Cp*Ir(Cab(S,S))], [(p-cymene)Ru(Cab(S,S))] (Cp* = pentamethylcyclopentadienyl) gives corresponding mononuclear 18e dithiolate complexes of the type [LM(Cab(E,E))(NHC)]: [Cp*M(Cab(S,S))(1-ethenyl-3-methylimidazolin-2-ylidene)] (M = Ir (2), Rh (3)), [Cp*Rh(Cab(E,E))(3-methyl-1-picolyimidazolin-2-ylidene)] [E = S (6), Se (7)], [(p-cymene)Ru(Cab(S,S))(NHC)] [NHC = 1-ethenyl-3-methylimidazolin-2-ylidene (4), 3-methyl-1-picolyimidazolin-2-ylidene (8)], whereas bis-NHC give centrosymmetric binuclear complexes [{Cp*M(Cab(S,S))}(2)(1,1'-dimethyl-3,3'-methylene(imidazolin-2-ylidene))] [M = Rh (10), Ir (11)]. The complexes were characterized by IR, NMR spectroscopy and elemental analysis. In addition, X-ray structure analyses were performed on complexes 2-4, 6, 8, 10 and 11.

20.
Dalton Trans ; (34): 3792-7, 2007 Sep 14.
Artigo em Inglês | MEDLINE | ID: mdl-17712445

RESUMO

The reaction of the 16-electron "pseudo-aromatic" complex Cp*Ir[Se2C2(B10H10)] (1, Cp* = eta5-C5Me5) with [Ir(cod)(micro-OC2H5)]2 leads to the trinuclear iridium complexes {(cod)Ir[Se2C2(B10H8)(OC2H5)]}Ir{[Se2C2(B10H10)]IrCp*} (2), {(cod)Ir[Se2C2(B10H8)(OC2H5)]}Ir{[Se2C2(B10H9)]IrCp*} (3), {Cp*Ir[Se2C2(B10H9)]}{IrSe(2)[C2(B10H9)(OC2H5)]}{[Se2C2(B10H10)] IrCp*} (4) and one mononuclear complex Cp*Ir[Se2C2(B10H8)(OC2H5)(2)] (5). The reactivity of 2 was investigated and revealed that transformation from 2 to 3 occurred thermally in solution. The transoid complex 2 (with the carborane diselenolato units in trans position) can be converted in nearly 90% yield to the cisoid complex 3. In complexes 2, 3, two diselenolato carborane ligands bridge the Ir(3) core, which consists of Ir-Ir metal bonds. Compared with transoid 2, the cisoid 3 contains two iridium-boron bonds. Complex 4 consists of three different coordination environment carborane ligands (Ir-B(cluster): {Cp*Ir[Se2C2(B10H9)]}, O-B(cluster): {[Se2C2(B10H9)](OC2H5)}, and intact carborane: {Cp*Ir[Se2C2 (B10H10)]}) without the presence of a metal-metal bond. Analogous reaction of 1 with [Ir(cod)(micro-OCH(3))](2) results in formation of the trinuclear complex {Cp*Ir[Se2C2(B10H9)]}{IrSe(2)[C2(B10H9)(OCH3)]}{[Se2C2(B10H10)]IrCp*} (6) and mononuclear complex Cp*Ir[Se2C2(B10H8)(OCH3)(2)] (7). The structures of 2, 3, 4, 5, 6 and 7 have been determined by crystallographic studies.

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