CBS-Q and DFT calculations of lithium and sodium cations affinities and basicities of 60 organic molecules

2016 ◽  
Vol 1091 ◽  
pp. 169-175 ◽  
Author(s):  
Younes Valadbeigi
Keyword(s):  
Dft Calculations ◽  
Organic Molecules ◽  
Sodium Cations

Competition between coordination bonds and hydrogen bonding interactions in solvatomorphs of copper(II), cadmium(II) and cobalt(II) complexes with 2,2′-bipyridyl and acetate

2019 ◽  
Vol 234 (2) ◽  
pp. 119-128 ◽  
Author(s):  
José Antônio do Nascimento Neto ◽  
Cameron Capeletti da Silva ◽  
Leandro Ribeiro ◽  
Ana Karoline Silva Mendanha Valdo ◽  
Felipe Terra Martins
Keyword(s):  
Hydrogen Bonding ◽  
Dft Calculations ◽  
Organic Molecules ◽  
Energy Difference ◽  
Water Molecules ◽  
Coordination Numbers ◽  
Lattice Water ◽  
Hydrogen Bonding Interactions ◽  
Metal Organic ◽  
Coordination Bonds

Abstract The delicate balance among conformation, coordination bonds and hydrogen bonding has been probed in solvatomorphs of known metal-organic molecules synthesised from copper(II), cadmium(II) and cobalt(II) with acetate (OAc) and 2,2′-bipyridine (bipy). The Cu(OAc)2(bipy) complex, isolated as a pentahydrate, has the acetate ligands oriented to opposite sides of the coordination square plane. DFT calculations show the energy difference between this structure and a syn form amount to approximately 16 kJ/mol. The presence of lattice water enables the formation of O–H···O hydrogen bonds with the acetate ligands. Different coordination numbers and energies are found as a function of the number of water molecules co-crystallising in the Cd(OAc)2(bipy)(OH2)·3H2O and [Co(OAc)(bipy)2](OAc)·3H2O complexes.

An INS study of entrapped organic cations within the micropores of zeolite RTH

2016 ◽  
Vol 18 (26) ◽  
pp. 17244-17252 ◽  
Author(s):  
Tetiana Lemishko ◽  
Jorge Simancas ◽  
Manuel Hernández-Rodríguez ◽  
Mónica Jiménez-Ruiz ◽  
German Sastre ◽  
...  
Keyword(s):  
Dft Calculations ◽  
Organic Molecules ◽  
Organic Cations

INS experiments and DFT calculations allow identifying rotational constraints of organic molecules occluded in zeolite micropores.

scholarly journals Effect of an Al(III) Complex on the Regio- and Stereoisomeric Formation of Bicyclic Organic Carbonates

2020 ◽  
Author(s):  
Cristina Maquilón ◽  
Bart Limburg ◽  
Victor Laserna ◽  
Diego Garay-Ruiz ◽  
Joan González Fabra ◽  
...  
Keyword(s):  
Carbon Dioxide ◽  
Dft Calculations ◽  
Organic Molecules ◽  
Solid Phase ◽  
Starting Material ◽  
X Ray ◽  
Epoxy Alcohol ◽  
Organic Carbonates ◽  
Presence And Absence

Valorization of carbon dioxide into organic molecules using catalytic approaches has witnessed an upsurge in recent years. Here, the influence of an Al(III) aminotriphenolate complex on the regio- and stereo-chemical features of the coupling between carbon dioxide and a cyclic epoxy alcohol has been studied. Three distinct bicyclic carbonate products were produced from a single starting material depending on the catalytic conditions. The proposed carbonate configurations were examined by solution and solid phase techniques including NMR spectroscopic and X-ray crystallographic analyses. Control experiments combined with DFT calculations provide a rationale for the distinct catalytic manifolds observed in the presence and absence of the Al(III) complex.

scholarly journals From Colloidal Dispersions of Zeolite Monolayers to Effective Solid Catalysts in Transformations of Bulky Organic Molecules: Role of Freeze-Drying and Dialysis

Molecules ◽  
2021 ◽  
Vol 26 (7) ◽  
pp. 2076
Author(s):  
Katarzyna Kałahurska ◽  
Pawel P. Ziemiański ◽  
Wieslaw J. Roth ◽  
Barbara Gil
Keyword(s):  
Ammonium Nitrate ◽  
Freeze Drying ◽  
Organic Molecules ◽  
Layer Structure ◽  
Acid Sites ◽  
Test Reaction ◽  
Solid Catalysts ◽  
External Acid Sites ◽  
Sodium Cations ◽  
Freeze Dried

We investigated the properties and catalytic activity of zeolites with MWW topology obtained by unprecedented liquid exfoliation of the MCM-56 zeolite into solutions of monolayers and isolation/reassembly of the dispersed layers by various methods, with optional purification by dialysis or ammonium exchange. The layers were recovered by flocculation with alcohol or ammonium nitrate and freeze-drying. Flocculation alone, even with ammonium nitrate, did not ensure removal of residual sodium cations resulting in catalysts with low activity. Dialysis of the solutions with dispersed monolayers proved to be efficient in removing sodium cations and preserving microporosity. The monolayers were also isolated as solids by freeze-drying. The highest BET area and pore volume obtained with the freeze-dried sample confirmed lyophilization efficiency in preserving layer structure. The applied test reaction, Friedel–Crafts alkylation of mesitylene, showed high benzyl alcohol conversion due to increased concentration of accessible acid centers caused by the presence of secondary mesoporosity. The applied treatments did not change the acid strength of the external acid sites, which are the most important ones for converting bulky organic molecules. Zeolite acidity was not degraded in the course of exfoliation into monolayers, showing the potential of such colloid dispersions for the formation of active catalysts.

Synthesis and Catalytic Evaluation of Ferrierite-Related Materials Synthesized in the Presence of co-Structure Directing Agents

2008 ◽  
Vol 73 (8-9) ◽  
pp. 1089-1104 ◽  
Author(s):  
Raquel García ◽  
Ana Belén Pinar ◽  
Carlos Márquez-Alvarez ◽  
Enrique Sastre ◽  
Joaquín Pérez-Pariente
Keyword(s):  
Catalytic Activity ◽  
Organic Molecules ◽  
Organic Cation ◽  
Zeolite Synthesis ◽  
Structure Directing Agent ◽  
Sodium Cations ◽  
Systematic Exploration ◽  
Structure Directing Agents

We report on the systematic exploration of zeolite synthesis using a combination of organic molecules of different size. The effect of changing the co-structure directing agent, co-SDA, (tetramethylammonium or quinuclidine) and its replacement by sodium cations, when used together with the bulky organic cation 1-benzyl-1-methylpyrrolidinium (bmp) is analyzed and compared with preparations where bmp is replaced by the related cation (S)-1-benzyl-2-hydroxymethyl-1-methylpyrrolidinium (bmprol). The tendency to direct the synthesis to ferrierite or ferrierite-like materials depending on the particular combination of bulky organic cation and co-SDA is discussed. The catalytic activity of some of the materials synthesized was tested in the isomerization of m-xylene.

Understanding the insertion reactions of CO2, aldehyde and alkene into Cu–X (X = B, C, O) bonds

2021 ◽  
Author(s):  
Xueying Guo ◽  
Zhenyang Lin
Keyword(s):  
Dft Calculations ◽  
Organic Molecules ◽  
Insertion Reactions ◽  
Relative Preference

The relative preference of different unsaturated organic molecules (CO2, PhCHO and styrene) for insertion into different Cu–X (X = B, C, O) bonds has been systematically examined with the aid of DFT calculations.

scholarly journals Effect of an Al(III) Complex on the Regio- and Stereoisomeric Formation of Bicyclic Organic Carbonates

2020 ◽  
Author(s):  
Cristina Maquilón ◽  
Bart Limburg ◽  
Victor Laserna ◽  
Diego Garay-Ruiz ◽  
Joan González Fabra ◽  
...  
Keyword(s):  
Carbon Dioxide ◽  
Dft Calculations ◽  
Organic Molecules ◽  
Solid Phase ◽  
Starting Material ◽  
X Ray ◽  
Epoxy Alcohol ◽  
Organic Carbonates ◽  
Presence And Absence

Valorization of carbon dioxide into organic molecules using catalytic approaches has witnessed an upsurge in recent years. Here, the influence of an Al(III) aminotriphenolate complex on the regio- and stereo-chemical features of the coupling between carbon dioxide and a cyclic epoxy alcohol has been studied. Three distinct bicyclic carbonate products were produced from a single starting material depending on the catalytic conditions. The proposed carbonate configurations were examined by solution and solid phase techniques including NMR spectroscopic and X-ray crystallographic analyses. Control experiments combined with DFT calculations provide a rationale for the distinct catalytic manifolds observed in the presence and absence of the Al(III) complex.

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