Controlled translocation of palladium(ii) within a 22 ring atom macrocyclic ligand

2014 ◽  
Vol 43 (45) ◽  
pp. 17006-17016 ◽  
Author(s):  
Michael G. Burgess ◽  
M. Naveed Zafar ◽  
Stephen T. Horner ◽  
George R. Clark ◽  
L. James Wright
Keyword(s):  
Macrocyclic Ligand ◽  
Tail Region ◽  
Ring Atom

Palladium can be directed to coordinate to the “tail” region of the macrocycle H4L to give 3b. Translocation of the palladium from the tail coordination pocket to the head coordination pocket occurs on treatment with amines such as n-BuNH2 to give 4.

Azaoxa Macrocyclic and Acyclic Complexesof Lanthanides

1998 ◽  
Vol 63 (3) ◽  
pp. 363-370 ◽  
Author(s):  
Violetta Patroniak-Krzyminiewska ◽  
Wanda Radecka-Paryzek
Keyword(s):  
Schiff Base ◽  
Spectral Data ◽  
Macrocyclic Ligand ◽  
Lanthanide Ions ◽  
H Nmr ◽  
Elemental Analyses ◽  
Acyclic Complexes ◽  
Schiff Base Cyclocondensation

The template reactions of 2,6-diacetylpyridine with 3,6-dioxaoctane-1,8-diamine in the presence of dysprosium(III), thulium(III) and lutetium(III) chlorides and erbium(III) perchlorate produce the complexes of 15-membered macrocyclic ligand with an N3O2 set of donor atoms as a result of the [1+1] Schiff base cyclocondensation. In contrast, analogous reactions involving the lighter lanthanide ions (lanthanum(III), samarium(III) and europium(III)) yield the acyclic complexes with terminal acetylpyridyl groupings as products of the partial [2+1] condensation. The complexes were characterized by spectral data (IR, UV-VIS, 1H NMR, MS), and thermogravimetric and elemental analyses.

Anion effect on alkali ion-crown complex formation in a moderately concentrated solutions: A sensitive probe of hidden interionic interactions operating in dissociating protic solvents

1990 ◽  
Vol 55 (5) ◽  
pp. 1149-1161
Author(s):  
Jiří Závada ◽  
Václav Pechanec ◽  
Oldřich Kocián
Keyword(s):  
Hydrogen Bond ◽  
Complex Formation ◽  
Charge Density ◽  
Macrocyclic Ligand ◽  
Simple Explanation ◽  
Anion Effect ◽  
Protic Solvents ◽  
The Individual ◽  
Alkali Salts ◽  
Alkali Ion

A powerful anion effect destabilizing alkali ion-crown complex formation has been found to operate in moderately concentrated protic (H2O, CH3OH, C2H5OH) solution, following the order HO- > AcO- > Cl- > Br- > NO3- > I- > NCS-. Evidence is provided that the observed effect does not originate from ion-pairing. A simple explanation is provided in terms of concordant hydrogen bond bridges of exalted stability between the gegenions, M+···OR-H···(OR-H)n···OR-H···A-. It is proposed that encapsulation of alkali ion by the macrocyclic ligand leads to a dissipation of the cation charge density destroying its ability to participate in the hydrogen bond bridge. An opposition against the alkali ion-crown complex formation arises accordingly in the solution in dependence on strength of the hydrogen bridge; for a given cation, the hydrogen bond strength increases with increasing anion charge density from NCS- to HO-(RO-). It is pointed out, at the same time, that the observed anion effect does not correlate with the known values of activity coefficients of the individual alkali salts which are almost insensitive to anion variation under the investigated conditions. As a resolution of the apparent paradoxon it is proposed that, in absence of the macrocyclic ligand, the stabilizing (concordant) bonding between the gegenions is nearly balanced by a destabilizing (discordant) hydrogen bonding between the ions of same charge (co-ions). Intrinsic differences among the individual salts are thus submerged in protic solvents and become apparent only when the concordant bonding is suppressed in the alkali ion-crown complex formation.

A New Host Lattice Built of the Werner-Type Copper(I,II) Cyanide Complex Involving a Macrocyclic Ligand

1998 ◽  
Vol 63 (5) ◽  
pp. 622-627 ◽  
Author(s):  
Hidetaka Yuge ◽  
Takayoshi Soma ◽  
Takeshi Ken Miyamoto
Keyword(s):  
Macrocyclic Ligand ◽  
Host Lattice ◽  
Macrocyclic Complex ◽  
Monoclinic Space Group ◽  
Cyanide Complex ◽  
New Host ◽  
Space Group

Crystals of a new clathrate [CuII(hmtd)CuI(CN)3]·CH2Cl2 were afforded from a Me2CO-EtOH-CH2Cl2 solution of a macrocyclic complex CuII(hmtd)CuI(CN)3·2 H2O (hmtd = 5,7,7,12,14,14-hexamethyl- 1,4,8,11-tetraazacyclotetradeca- 4,11-diene). It crystallizes in the monoclinic space group P21/n, a = 7.936(5), b = 18.717(4), c = 17.783(6) Å, β = 98.55(4)°, Z = 4, R = 0.0558 for 1 870 reflections. Unprecedentedly, only one of the three nitrogen-ends of a CuI(CN)3 moiety is coordinated to the square-pyramidal Cu(II) center. The guest CH2Cl2 molecules are captured in the channel between the potlid-shaped [CuII(hmtd)CuI(CN)3] molecules.

Silyl–Hydrosilane Exchange at a Magnesium Triphenylsilyl Complex Supported by a Cyclen-DerivedNNNN-Type Macrocyclic Ligand

2017 ◽  
Vol 56 (24) ◽  
pp. 14979-14990 ◽  
Author(s):  
Lara E. Lemmerz ◽  
Valeri Leich ◽  
Daniel Martin ◽  
Thomas P. Spaniol ◽  
Jun Okuda
Keyword(s):  
Macrocyclic Ligand

Crystal structure of a PrIII complex with a novel macrocyclic ligand

Polyhedron ◽  
1997 ◽  
Vol 16 (15) ◽  
pp. 2697-2700 ◽  
Author(s):  
Janfang Ma ◽  
Chunji Niu ◽  
Shulan Meng ◽  
Yonghua Lin ◽  
Yan Xing ◽  
...  
Keyword(s):  
Crystal Structure ◽  
Macrocyclic Ligand

scholarly journals Template synthesis and characterization of biologically active transition metal complexes comprising 14-membered tetraazamacrocyclic ligand

2010 ◽  
Vol 75 (2) ◽  
pp. 217-228 ◽  
Author(s):  
Dharmpal Singh ◽  
Krishan Kumar ◽  
Ramesh Kumar ◽  
Jitender Singh
Keyword(s):  
Magnetic Measurements ◽  
Macrocyclic Ligand ◽  
Salmonella Typhi ◽  
Molar Conductance ◽  
Biologically Active ◽  
Distorted Octahedral Geometry ◽  
Bacterial Strains ◽  
In Vitro Antibacterial Activity ◽  
Active Transition

A novel series of complexes of the type [M(C28H24N4)X2], where M = Co(II), Ni(II), Cu(II), Zn(II) and Cd(II), X = Cl-, NO3 -, CH3COO- and (C28H24N4) corresponds to the tetradentate macrocyclic ligand, were synthesized by template condensation of 1,8-diaminonaphthalene and diacetyl in the presence of divalent metal salts in methanolic medium. The complexes were characterized by elemental analyses, conductance and magnetic measurements, as well as by UV/Vis, NMR, IR and MS spectroscopy. The low values of the molar conductance indicate non-electrolyte type of complexes. Based on these spectral data, a distorted octahedral geometry may be proposed for all of these complexes. All the synthesized macrocyclic complexes were tested for in vitro antibacterial activity against some pathogenic bacterial strains, viz Bacillus cereus, Salmonella typhi, Escherichia coli and Staphylococcus aureus. The MIC values shown by the complexes against these bacterial strains were compared with the MIC shown by the standard antibiotics linezolid and cefaclor.

A Macrocyclic Ligand Framework That Improves Both the Stability and T1-Weighted MRI Response of Quinol-Containing H2O2 Sensors

2021 ◽  
Author(s):  
Sana Karbalaei ◽  
Erik Knecht ◽  
Alicja Franke ◽  
Achim Zahl ◽  
Alexander C. Saunders ◽  
...  
Keyword(s):  
Macrocyclic Ligand ◽  
The Stability
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