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1.
Inorg Chem ; 55(13): 6504-10, 2016 Jul 05.
Article in English | MEDLINE | ID: mdl-27308962

ABSTRACT

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.
Article in English | MEDLINE | ID: mdl-26595532

ABSTRACT

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.
Article in English | MEDLINE | ID: mdl-25329984

ABSTRACT

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.
Article in English | MEDLINE | ID: mdl-25215429

ABSTRACT

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.

6.
Dalton Trans ; 41(38): 11657-62, 2012 Oct 14.
Article in English | MEDLINE | ID: mdl-22854827

ABSTRACT

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.

7.
Chem Commun (Camb) ; 48(37): 4435-7, 2012 May 11.
Article in English | MEDLINE | ID: mdl-22456470

ABSTRACT

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.

8.
Chem Commun (Camb) ; 47(25): 7197-9, 2011 Jul 07.
Article in English | MEDLINE | ID: mdl-21625720

ABSTRACT

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.


Subject(s)
Dicarboxylic Acids/chemistry , Hexanes/chemistry , Organometallic Compounds/chemistry , Triazoles/chemistry , Zinc/chemistry , Adsorption , Isomerism , Ligands , Models, Molecular , Molecular Conformation
9.
Org Lett ; 13(7): 1864-7, 2011 Apr 01.
Article in English | MEDLINE | ID: mdl-21391556

ABSTRACT

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.


Subject(s)
Cyclopentanes/chemistry , Lamiaceae/chemistry , Sesterterpenes/chemistry , Animals , Cyclization , Cyclopentanes/pharmacology , Lepidoptera/drug effects , Models, Molecular , Molecular Structure , Plant Leaves/chemistry , Sesterterpenes/pharmacology , Stereoisomerism
10.
Dalton Trans ; 39(44): 10712-8, 2010 Nov 28.
Article in English | MEDLINE | ID: mdl-20941428

ABSTRACT

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.

11.
J Org Chem ; 75(14): 4796-805, 2010 Jul 16.
Article in English | MEDLINE | ID: mdl-20568786

ABSTRACT

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.


Subject(s)
Amino Acids/chemistry , Cyclopropanes/chemistry , Dipeptides/chemistry , Nitrogen/chemistry , Oligopeptides/chemical synthesis , Oxygen/chemistry , Circular Dichroism , Crystallography, X-Ray , Cyclopropanes/chemical synthesis , Models, Molecular , Molecular Conformation , Molecular Sequence Data , Molecular Structure , Nuclear Magnetic Resonance, Biomolecular , Oligopeptides/chemistry
12.
Chem Commun (Camb) ; 46(20): 3556-8, 2010 May 28.
Article in English | MEDLINE | ID: mdl-20386861

ABSTRACT

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.


Subject(s)
Iridium/chemistry , Macrocyclic Compounds/chemical synthesis , Organometallic Compounds/chemical synthesis , Crystallography, X-Ray , Macrocyclic Compounds/chemistry , Models, Molecular , Molecular Structure , Organometallic Compounds/chemistry , Stereoisomerism
13.
Acta Crystallogr C ; 66(Pt 4): m97-100, 2010 Apr.
Article in English | MEDLINE | ID: mdl-20354296

ABSTRACT

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.


Subject(s)
Manganese/chemistry , Organometallic Compounds/chemistry , Polymers/chemistry , Crystallography, X-Ray , Hydrogen Bonding , Ligands , Molecular Structure
14.
Chem Commun (Camb) ; 46(7): 1100-2, 2010 Feb 21.
Article in English | MEDLINE | ID: mdl-20126726

ABSTRACT

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.

15.
Chem Commun (Camb) ; (3): 350-2, 2008 Jan 21.
Article in English | MEDLINE | ID: mdl-18399204

ABSTRACT

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.

16.
Dalton Trans ; (34): 3792-7, 2007 Sep 14.
Article in English | MEDLINE | ID: mdl-17712445

ABSTRACT

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.

17.
Chemistry ; 13(15): 4146-54, 2007.
Article in English | MEDLINE | ID: mdl-17397024

ABSTRACT

Attempts to create metal-organic frameworks (MOFs) with zeolitic topologies, metal (zinc(II) and cobalt(II)) imidazolates have repeatedly been used as the metal-organic motifs of inorganic silicate analogues. By modulating the synthetic strategy based on the solvothermal and liquid diffusion method, seven further MOFs (including at least three zeolitic MOFs) of zinc(II) imidazolates, [Zn(im)2.x G] (G=guest molecule, x=0.2-1) 1 a-7 a, have been successfully synthesized. Of these, 1 a-3 a are isostructural with the previously reported cobalt analogues 1 b-3 b, respectively, while 4 a-7 a are new members of the metal imidazolate MOF family. Complex 4 a exhibits a structure related to silicate CaAl2Si2O8 of CrB4 topology, but with a higher network symmetry; complex 5 a has a structure with zeolitic DFT topology that was discovered in zeolite-related materials of DAF-2, UCSB-3, and UCSB-3GaGe; complex 6 a demonstrates an unprecedented zeolite-like topology with one dimensional channels with 10-rings; and 7 a displays a structure of natural zeolite GIS (gismondine) topology. All of these polymorphous MOFs were created only by using certain solvents as structure-directing agents (SDAs). Further extensive metal-organic frameworks with zeolitic topologies can be envisaged if other solvents were to be used.

18.
Chemistry ; 13(1): 188-95, 2007.
Article in English | MEDLINE | ID: mdl-17042047

ABSTRACT

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.

19.
Chem Commun (Camb) ; (2): 162-4, 2006 Jan 14.
Article in English | MEDLINE | ID: mdl-16372092

ABSTRACT

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.


Subject(s)
Boron Compounds/chemistry , Organometallic Compounds/chemistry , Organometallic Compounds/chemical synthesis , Porphyrins/chemistry , Crystallography, X-Ray , Ligands , Models, Molecular
20.
Chemistry ; 11(24): 7342-50, 2005 Dec 09.
Article in English | MEDLINE | ID: mdl-16187373

ABSTRACT

The 16-electron half-sandwich complex [Cp*Ir[S2C2(B10H10)]] (Cp* = eta5-C5Me5) (1a) reacts with [[Rh(cod)(mu-Cl)]2] (cod = cycloocta-1,5-diene, C8H12) in different molar ratios to give three products, [[Cp*Ir[S2C2(B10H9)]]Rh(cod)] (2), trans-[[Cp*Ir[S2C2(B10H9)]]Rh[[S2C2(B10H10)]IrCp*]] (3), and [Rh2(cod)2[(mu-SH)(mu-SC)(CH)(B10H10)]] (4). Complex 3 contains an Ir2Rh backbone with two different Ir-Rh bonds (3.003(3) and 2.685(3) angstroms). The dinuclear complex 2 reacts with the mononuclear 16-electron complex 1a to give 3 in refluxing toluene. Reaction of 1a with [W(CO)3(py)3] (py = C5H5N) in the presence of BF3.EtO2 leads to the trinuclear cluster [[Cp*Ir[S2C2(B10H10)]]2W(CO)2] (5) together with [[Cp*Ir(CO)[S2C2(B10H10)]]W(CO)5] (6), and [Cp*Ir(CO)[S2C2(B10H10)]] (7). Analogous reactions of [Cp*Rh[S2C2(B10H10)]] (1 b) with [[Rh(cod)(mu-Cl)]2] were investigated and two complexes cis-[[Cp*Rh[S2C2(B10H10)]]2Rh] (8) and trans-[[Cp*Rh[S2C2(B10H10)]]2Rh] (9) were obtained. In refluxing THF solution, the cisoid 8 is converted in more than 95 % yield to the transoid 9. All new complexes 2-9 were characterized by NMR spectroscopy (1H, 11B NMR) and X-ray diffraction structural analyses are reported for complexes 2-5, 8, and 9.

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