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1.
Artigo em Inglês | MEDLINE | ID: mdl-26830801

RESUMO

A supramolecular compound, catena-poly{[Cu2(1,3-µ2-(1a))2(µ2-ter)2(H2O)2]n·(6H2O)n} (1) has been synthesized using (1a) [(1a = N(1),N(3),N(5)-trimethyl-N(1),N(3),N(5)-tris((pyridin-4-yl)methyl)-1,3,5-benzene tricarboxamide] and terephthalate (ter) as the pillaring unit by self-assembly. The terephthalate units are connected by copper(II) ions forming a single strand, while a pair of such strands are then linked by (1a) via two pyridyl terminal arms bound to copper(II) nodes on either side forming a one-dimensional double stranded assembly propagating along the c axis. The compound crystallizes in the Fdd2 space group. The cavity created in the interior of this double strand assembly trap six water molecules and are stabilized by hydrogen bonding with the host. The arrangement of the pair of acyclic water trimers in isolated cavities of (1) is such that it resembles a closed-bracket-like formation. The Hirshfeld surface analysis of (1) reveals the presence of strong intermolecular hydrogen-bonding interactions between one-dimensional ladder-like units and with the water trimer in the host cavity. The copper(II)-containing coordination polymer also acts as an efficient catalyst for the Glaser-Hay homo-coupling reaction.

2.
Inorg Chem ; 47(19): 8807-12, 2008 Oct 06.
Artigo em Inglês | MEDLINE | ID: mdl-18781729

RESUMO

Either an S 8 symmetrical 48-membered hexadecanuclear or an S 10 symmetrical 60-membered icosanuclear manganese metallamacrocycle was self-assembled using a manganese ion and a ditopic pentadentate ligand. This was either N-4-phenylbenzoylsalicylhydrazide (H 3pbshz) containing a rigid rod-shaped, bulky biphenyl residue as a terminal N-acyl group or N-3,3-diphenylpropionylsalicylhydrazide (H 3dppshz) containing a flexible beta-branched N-acyl group, but with two sterically bulky phenyl residues at the Cbeta position. The backbone of these metal-organic assemblies is a repeating unit consisting of a -[Mn-N-N-] link that extends to complete either the 48-membered cyclic structure involving 16 manganese(III) centers and 16 ditopic linker ligands or the 60-membered cyclic structure involving 20 manganese(III) centers and 20 ditopic linker ligands (depending on the ligand used). Even though the nuclearity of the metallamacrocycles was different, the successive manganese centers were in the same chiral sequence, ...(LambdaLambdaDeltaDelta)(LambdaLambdaDeltaDelta)....

3.
Dalton Trans ; (1): 131-6, 2008 Jan 07.
Artigo em Inglês | MEDLINE | ID: mdl-18399239

RESUMO

An S6-symmetric hexanuclear gallium metalladiazamacrocycle, [Ga(III)(6)L2(6)S6] with a -(lamda delta)(lamda delta)-chiral sequence and an S-symmetric hexadecanuclear manganese metalladiazamacrocycle, [Mn(III)(16)L2(16)S16] with a -(lamda lamda delta delta)(lamda lamda delta delta)-chiral sequence were prepared using the same N2-trans-cinnamoyl-2-hydroxy-3-naphthoylhydrazide (H3L2) as a bridging pentadentate ligand between the metal centers for the formation of a macrocyclic system.

4.
Inorg Chem ; 46(24): 10208-13, 2007 Nov 26.
Artigo em Inglês | MEDLINE | ID: mdl-17973371

RESUMO

Discrete metal-organic polyhedra (MOP) with nanosized cavities and/or clusters of MOP could be prepared when C3-symmetric facial ligands and a potential hexatopic Cu(II) ion are combined in the presence of perchlorate as a weak linker, while similar reaction conditions in the presence of a nitrate linker led to extended metal-organic frameworks made of MOP as supramolecular building blocks.

5.
Dalton Trans ; (46): 5412-8, 2007 Dec 14.
Artigo em Inglês | MEDLINE | ID: mdl-18026590

RESUMO

Two topologically different metallamacrocycles--S8 symmetric octanuclear gallium(III) metalladiazamacrocycle and pseudo-D4 symmetric octanuclear gallium(III) metalladiazamacrocycle--could be prepared using two similar heteroditopic bridging ligands having asymmetrical tridentate-bidentate binding residues.

7.
Chem Commun (Camb) ; (35): 3699-701, 2006 Sep 21.
Artigo em Inglês | MEDLINE | ID: mdl-17047816

RESUMO

An extended 36-membered dodecanuclear manganese metallamacrocycle with S12 symmetry has been synthesized using the ligand N-cyclohexanoylsalicylhydrazide (H3chxshz) by a self-assembly that accommodates a cyclooctane of conformationally strained S4 symmetry in its hydrophobic cavity.

8.
Inorg Chem ; 45(20): 7991-3, 2006 Oct 02.
Artigo em Inglês | MEDLINE | ID: mdl-16999391

RESUMO

A novel S4-symmetric icosanuclear manganese metalladiazamacrocycle was synthesized using a pentadentate ligand, N-3-phenyl-trans-2-propenoylsalicylhydrazide (H3L), that has a rigid and bulky terminal N-acyl group. A 20 cyclic repeat of an--(Mn-N-N)--linkage resulted in a highly puckered diaza-bridged 60-membered icosanuclear metallamacrocycle. The steric interaction between the ligands in the cyclic system leads to five consecutive Mn(III) centers in a chemically different--(Mn(A)Mn(B)Mn(C)Mn(D)Mn(E))--environment, with the chiralities of the metal centers being in a rather complicated--(LambdaLambdaDeltaLambdaLambda)(DeltaDeltaLambdaDeltaDelta)--sequence.

9.
J Am Chem Soc ; 128(11): 3530-1, 2006 Mar 22.
Artigo em Inglês | MEDLINE | ID: mdl-16536521

RESUMO

The face-driven corner-linked truncated octahedral nanocages, [Pd6L8]12+ (1, L1 = N,N',N' '-tris(3-pyridinyl)-1,3,5-benzenetricarboxamide; 2, L2 = N,N',N' '-tris(4-pyridinylmethyl)-1,3,5-benzenetricarboxamide), were prepared with eight C3-symmetric tridentate ligands and six square planar tetratopic palladium(II) ions. The combination of the nitrogen donor atom at a approximately 120 degrees kink position of the carboxamido pyridinyl group and the tilted pyridyl versus the facial plane of the ligands can provide the needed curvature for the formation of octahedral cages. The nitrogen atoms can coordinate to the square planar palladium(II) ions to form kinks with approximately 120 degrees angles at the C4-symmetric square planar corners of the truncated octahedron. Depending on the conformation of the ligand, L1, two different truncated octahedral cages of around 2.4 nm in diameters were formed. The major form of 1 with syn-conformational ligands has a cavity volume of approximately 1600 A3. The cage has 12 ports (3.4 x 3.5 A2) at all edges of the octahedron. The minor form of cage 1 with anti-conformational ligands has a slightly increased cavity volume ( approximately 1900 A3) and port size (3.3 x 8.0 A2). The insertion of a methylene group in L2 has not only increased the cavity volume of 2 to approximately 2200 A3 but also enlarged the port size to 4.1 x 8.0 A2. However, an atomic force microscopy (AFM) study of cage 2 showed that the cages had a height of 1.8 +/- 0.1 nm. This value is about 30% smaller than the calculated size of 2.6 nm from the crystal structure. This tip-induced decrease in height in cage 2 suggests the nonrigidity of cage 2.


Assuntos
Nanoestruturas/química , Compostos Organometálicos/química , Paládio/química , Amidas/química , Modelos Moleculares , Piridinas/química , Ácidos Tricarboxílicos/química
10.
Inorg Chem ; 44(20): 7109-21, 2005 Oct 03.
Artigo em Inglês | MEDLINE | ID: mdl-16180873

RESUMO

Hexanuclear, octanuclear, and decanuclear manganese metalladiazamacrocycles have been prepared by reacting a series of pentadentate ligands, N-acylsalicylhydrazides (N-(3-methylbutanoyl)salicylhydrazide (H(3)3-mbshz), N-(phenylacetyl)salicylhydrazide (H(3)pashz), N-(3,3-dimethylbutanoyl)salicylhydrazide (H(3)3-dmbshz), N-(2-methylpropanoyl)salicylhydrazide (H(3)2-mpshz), N-((R,S)-2-methylbutanoyl)salicylhydrazide (H(3)RS-2-mbshz), N-((S)-2-methylbutanoyl)salicylhydrazide (H(3)S-2-mbshz), and N-(2,2-dimethylpropanoyl)salicylhydrazide (H(3)2-dmpshz)), with manganese(II) acetate tetrahydrate. The self-assembled, supramolecular complexes assume a nearly planar cyclic structure with an -(Mn-N-N)(n) backbone and measure approximately 2.1, approximately 2.3, and approximately 2.6 nm in outer diameters for n = 6, 8, and 10, respectively. The chiralities of the manganese centers on the metalladiazamacrocycle occur in alternating ...LambdaDeltaLambdaDelta... configurations. While beta-branched N-acylsalicylhydrazides (H(3)3-mbshz, H(3)pashz, H(3)3-dmbshz) with a sterically flexible Calpha methylene group yield 18-membered hexanuclear manganese metalladiazamacrocycles of S(6) point group symmetry, alpha-branched N-acylsalicylhydrazides lead to 24-membered octanuclear manganese metalladiazamacrocycles or 30-membered decanuclear manganese metalladiazamacrocycles depending on the size of the N-acyl substituents. The alpha-branched H(3)2-mpshz ligand with the sterically least demanding isopropyl tail at the N-acyl position yields a 24-membered octanuclear manganese metalladiazamacrocycle of S(8) point group symmetry, but other alpha-branched N-acylsalicylhydrazides such as H(3)RS-2-mbshz, H(3)S-2-mbshz, and H(3)2-dmpshz lead to 30-membered decanuclear manganese metalladiazamacrocycles of S(10) point group symmetry. The magnetic properties of the metalladiazamacrocycles are characterized by a weak antiferromagnetic exchange interaction, with J(eff) = -8.5 to -3.8 K between the Mn(3+) ion spins with S = 2 in the cyclic system.

11.
Acta Crystallogr C ; 61(Pt 6): m284-6, 2005 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-15930666

RESUMO

The title compound, [Cu2(C17H17N4S)2Cl2], exhibits a dimeric structure related by a centre of symmetry. The monomers are linked to each other by the longest Cu-S apical distance observed to date among Cu(II) square-pyramidal complexes of N4-substituted thiosemicarbazones. Each Cu(II) atom deviates from the coordination square plane, which contains the pyridyl and imine N atoms, the thiolate S atom and the Cl- anion, towards the S atom of the adjacent monomer. The dimers pack in a zigzag manner through the crystal.


Assuntos
Compostos Organometálicos/química , Cristalização
12.
Chem Commun (Camb) ; (23): 2660-1, 2004 Dec 07.
Artigo em Inglês | MEDLINE | ID: mdl-15568055

RESUMO

A novel dodecanuclear manganese metalladiazamacrocycle was synthesized employing a new pentadentate ligand N-2-pentenoylsalicylhydrazide (H(3)tpeshz) by supramolecular self-assembly. The backbone of this metal-organic assembly is a repeating unit of an M-N-N-M linkage that extends to complete a 36-membered cyclic structure involving 12 manganese(III) centers. Successive manganese centers are in a chemically different ...ABABAB...-type environment while the chirality varies as ...LambdaLambdaDeltaDeltaLambdaLambda... . The unique arrangement of manganese centers results in a highly puckered metalladiazamacrocycle with an S(6)-point group symmetry.

13.
Spectrochim Acta A Mol Biomol Spectrosc ; 59(6): 1349-58, 2003 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-12659904

RESUMO

The spectral studies and structure of a ternary complex of copper(II) with 2-hydroxyacetophenone 3-hexamethyliminylthiosemicarbazonate (L(2-)) and 1,10-phenanthroline (phen) are reported. The thiosemicarbazone binds to the metal as a dianionic ONS-donor (L(2-)) ligand, and forms a complex of the stoichiometry [CuLphen]. The copper(II) complex was characterized by IR and UV/Vis spectroscopies, as well as by solid state room-temperature magnetic susceptibility. Spin Hamiltonian and bonding parameters of the compound are calculated from the EPR spectra. Computer simulation of EPR spectrum in DMF at 77 K aided the calculation of magnetic and bonding parameters of the compound. The structure of the compound is solved by single crystal X-ray diffraction. The geometry around copper is distorted square pyramidal.


Assuntos
Acetofenonas/química , Compostos Organometálicos/química , Fenantrolinas/química , Cobre/química , Espectroscopia de Ressonância de Spin Eletrônica , Ligação de Hidrogênio , Íons , Ligantes , Espectroscopia de Ressonância Magnética , Modelos Químicos , Modelos Moleculares , Espectrofotometria/métodos , Espectrofotometria Infravermelho , Temperatura , Tiossemicarbazonas/química , Raios Ultravioleta , Difração de Raios X
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