scholarly journals Can Donor Ligands Make Pd(OAc)2 a Stronger Oxidant? Access to Elusive Palladium(II) Reduction Potentials and Effects of Ancillary Ligands via Palladium(II)/Hydroquinone Redox Equilibria

2020 ◽  
Vol 142 (46) ◽  
pp. 19678-19688
Author(s):  
David L. Bruns ◽  
Djamaladdin G. Musaev ◽  
Shannon S. Stahl
Keyword(s):  
Donor Ligands ◽  
Ancillary Ligands ◽  
Reduction Potentials ◽  
Redox Equilibria

Flexible N-Donor Ligands Direct the Structural Characteristics of CoII Complexes: Syntheses, Structures, and Magnetic Properties

2019 ◽  
Vol 72 (5) ◽  
pp. 341 ◽  
Author(s):  
Yu-Ting Yang ◽  
Chang-Zheng Tu ◽  
Xiao-Lin Xu ◽  
Li-Li Xu ◽  
Bang-Ling Yan ◽  
...  
Keyword(s):  
Magnetic Properties ◽  
Coordination Polymers ◽  
Structural Characteristics ◽  
Donor Ligands ◽  
X Ray Diffraction ◽  
Thermal Stabilities ◽  
Ancillary Ligands ◽  
X Ray ◽  
Elemental Analyses ◽  
Bilayered Structure

Solvothermal reactions of 3,3′,5,5′-biphenyltetracarboxylic acid (H4BPTC) and cobalt(ii) ions in the presence of two different flexible N-donor ancillary ligands afford two novel coordination polymers, {[Co(BPTC)0.5(bix)]·H2O}n (1), {[Co(BPTC)0.5(bpp)]·3H2O}n (2) (bix=1,4-bis(imidazol-1-ylmethyl)benzene; bpp=1,3-bis(4-pyridyl)propane). Their structures have been determined by elemental analyses, IR spectra, single-crystal X-ray diffraction analyses, and powder X-ray diffraction. The pillared layered framework of 1 can be simplified to a (4,6)-connected net with a Schläfli symbol of (44·62)(44·69·82). Complex 2 manifests a bilayered structure, and can be simplified to a (4,4)-connected net with a Schläfli symbol of (55·8)(54·62). The thermal stabilities of both complexes and the magnetic behaviours of 1 are also discussed.

scholarly journals Effect of N-donor ancillary ligands on structural and magnetic properties of oxalate copper(ii) complexes

2014 ◽  
Vol 38 (4) ◽  
pp. 1611-1626 ◽  
Author(s):  
Anna Świtlicka-Olszewska ◽  
Barbara Machura ◽  
Jerzy Mroziński ◽  
Bożena Kalińska ◽  
Rafał Kruszynski ◽  
...  
Keyword(s):  
Magnetic Properties ◽  
Donor Ligands ◽  
Ancillary Ligands ◽  
Structural And Magnetic Properties ◽  
New Compounds

Through varying the auxiliary N-donor ligands nine new compounds have been synthesized and characterised structurally and spectroscopically. The magnetic properties of the complexes have been investigated and discussed in the context of their structures.

scholarly journals Heterogeneous catalitic activity of Novel Indium MOFs

2014 ◽  
Vol 70 (a1) ◽  
pp. C1227-C1227
Author(s):  
Lina Aguirre-Diaz ◽  
Marta Iglesias ◽  
Natalia Snejko ◽  
Enrique Gutierrez-Puebla ◽  
Maria Monge
Keyword(s):  
Topological Analysis ◽  
Gas Absorption ◽  
Lewis Acidity ◽  
Donor Ligands ◽  
Organic Transformations ◽  
Lewis Acid Catalysts ◽  
Ancillary Ligands ◽  
Network Topologies ◽  
Indium Compounds ◽  
2D Network

Generally, group IIIA metal-based polycarboxylates are less studied, compared with those of transition or rare earth metals. However, In-MOFs have received recently much attention due to their interesting network topologies, which are mainly owing to the variety of coordination modes (6, 7 or 8) in indium MOFs with O- and N-donor ligands. [1]. Some of In-MOFs exhibit an exceptional gas absorption, fluorescent, ion-exchange properties, and can be used as heterogeneous Lewis acid catalysts in various organic transformations. The high relevance of Indium materials in catalytic studies for important organic reactions led to development of indium MOFs. [2-3] Here we report the solvothermal synthesis, structural characterization, topological analysis and catalytic studies of six new indium-based MOFs using 5-(4-carboxy-2-nitrophenoxy)isophtalic acid (H3popha) together with N-donor ancillary ligands (Figure 1). The three indium compounds showing 3D networks are the following: [In8(OH)6(popha)6(H2O)4]·xH2O (1), [In2(popha)2(4,4-bipy)2] (2) and [In3(OH)3(popha)2(4,4'-bipy)2]·xH2O (3). Meanwhile, compounds with a 2D network have a composition [In(popha)(1,10-phen)]·xH2O (4), [In(popha)(1,10-phen)]·xH2O (5) and [In(popha)(2,2'-bipy)]·xH2O (6). The catalytic study performed using indium compounds 1-6 as catalysts in a Lewis acidity promoted organic reaction, allows for establishing a connection between the corresponding MOF network dimensionality and its catalytic behavior.

Cobaloxime-Based Double Complex Salts as Efficient and Versatile Catalysts for the Light-Driven Hydrogen Evolution Reaction

2020 ◽  
Author(s):  
Elisabeth Hofmeister ◽  
Jisoo Woo ◽  
Tobias Ullrich ◽  
Lydia Petermann ◽  
Kevin Hanus ◽  
...  
Keyword(s):  
Hydrogen Evolution ◽  
Hydrogen Evolution Reaction ◽  
Systematic Study ◽  
Cobalt Complexes ◽  
Spectroscopic Studies ◽  
Double Complex ◽  
Double Complex Salts ◽  
Noble Metal Catalysts ◽  
Reduction Potentials ◽  
Complex Salts

Cobaloximes and their BF<sub>2</sub>-bridged analogues have emerged as promising non-noble metal catalysts for the photocatalytic hydrogen evolution reaction (HER). Herein we report the serendipitous discovery that double complex salts such as [Co(dmgh)<sub>2</sub>py<sub>2</sub>]<sup>+</sup>[Co(dmgBPh<sub>2</sub>)<sub>2</sub>Cl<sub>2</sub>]<sup>-</sup> can be obtained in good yields by treatment of commercially available [Co(dmgh)<sub>2</sub>pyCl] with triarylboranes. A systematic study on the use of such double complex salts and their single salts with simple counterions as photocatalysts revealed HER activities comparable or superior to existing cobaloxime catalysts and suggests ample opportunities for this compound class in catalyst/photosensitizer dyads and immobilized architectures. Preliminary electrochemical and spectroscopic studies indicate that one key advantage of these charged cobalt complexes is that the reduction potentials as well as the electrostatic interaction with charged photosensitizers can be tuned.

Phosphoryl- and Phosphonium-Bridged Viologens as Stable Two- and Three-Electron Acceptors for Organic Electrodes

2020 ◽  
Author(s):  
Colin R. Bridges ◽  
Andryj M. Borys ◽  
Vanessa Béland ◽  
Joshua R. Gaffen ◽  
Thomas Baumgartner
Keyword(s):  
Molecular Weight ◽  
Organic Molecules ◽  
Electrode Materials ◽  
High Energy ◽  
Electron Acceptors ◽  
Low Molecular Weight ◽  
Reduction Potentials ◽  
Organic Electrode ◽  
High Reduction ◽  
High Specific Energy

Low molecular weight organic molecules that can accept multiple electrons at high<br>reduction potentials are sought after as electrode materials for high-energy sustainable batteries. To date their synthesis has been difficult, and organic scaffolds for electron donors significantly outnumber electron acceptors. Herein, we report two highly electron deficient phosphaviologen derivatives from a phosphorus-bridged 4,4-bipyridine and characterize their electrochemical properties. Phosphaviologen sulfide (PVS) and P-methyl phosphaviologen (PVM) accept two and three electrons at high reduction potentials, respectively. PVM can reversibly accept 3 electrons between 3-3.6 V vs. Li/Li+ with an equivalent molecular weight of 102 g/(mol e-) (262 mAh/g), making it a promising scaffold for sustainable organic electrode materials having high specific energy densities.

Xenon Trioxide Adducts of O-Donor Ligands; [(CH3)2CO]3XeO3, [(CH3)2SO]3(XeO3)2, (C5H5NO)3(XeO3)2, and [(C6H5)3PO]2XeO3

2018 ◽  
Author(s):  
Katherine Marczenko ◽  
James Goettel ◽  
Gary Schrobilgen
Keyword(s):  
Room Temperature ◽  
Triphenylphosphine Oxide ◽  
Donor Ligands ◽  
Mechanical Shock ◽  
X Ray Diffraction ◽  
X Ray ◽  
Oxygen Coordination ◽  
Xenon Trioxide ◽  
Distorted Octahedra ◽  
Coordination Spheres

Oxygen coordination to the Xe(VI) atom of XeO<sub>3</sub> was observed in its adducts with triphenylphosphine oxide, dimethylsulfoxide, pyridine-N-oxide, and acetone. The crystalline adducts were characterized by low-temperature, single-crystal X-ray diffraction and Raman spectroscopy. Unlike solid XeO<sub>3</sub>, which detonates when mechanically or thermally shocked, the solid [(C<sub>6</sub>H<sub>5</sub>)<sub>3</sub>PO]<sub>2</sub>XeO<sub>3</sub>, [(CH<sub>3</sub>)<sub>2</sub>SO]<sub>3</sub>(XeO<sub>3</sub>)<sub>2</sub>,<sub> </sub>and (C<sub>5</sub>H<sub>5</sub>NO)<sub>3</sub>(XeO<sub>3</sub>)<sub>2</sub> adducts are insensitive to mechanical shock, but undergo rapid deflagration when ignited by a flame. Both [(C<sub>6</sub>H<sub>5</sub>)<sub>3</sub>PO]<sub>2</sub>XeO<sub>3 </sub>and (C<sub>5</sub>H<sub>5</sub>NO)<sub>3</sub>(XeO<sub>3</sub>)<sub>2</sub> are air-stable whereas [(CH<sub>3</sub>)<sub>2</sub>SO]<sub>3</sub>(XeO<sub>3</sub>)<sub>2</sub> slowly decomposes over several days and [(CH<sub>3</sub>)<sub>2</sub>CO]<sub>3</sub>XeO<sub>3</sub> undergoes adduct dissociation at room temperature. The xenon coordination sphere of [(C<sub>6</sub>H<sub>5</sub>)<sub>3</sub>PO]<sub>2</sub>XeO<sub>3</sub> is a distorted square pyramid which provides the first example of a five-coordinate XeO<sub>3</sub> adduct. The xenon coordination spheres of the remaining adducts are distorted octahedra comprised of three Xe---O secondary contacts that are approximately trans to the primary Xe–O bonds of XeO<sub>3</sub>. Quantum-chemical calculations were used to assess the Xe---O adduct bonds, which are predominantly electrostatic σ-hole bonds between the nucleophilic oxygen atoms of the bases and the σ-holes of the xenon atoms.

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