scholarly journals Effect of ring rize on photoisomerization properties of stiff stilbene macrocycles

2019 ◽  
Vol 15 ◽  
pp. 2408-2418 ◽  
Author(s):  
Sandra Olsson ◽  
Óscar Benito Pérez ◽  
Magnus Blom ◽  
Adolf Gogoll
Keyword(s):  
Dft Calculations ◽  
Energy Difference ◽  
Carbon Chain ◽  
Experimental Results ◽  
Dft Study ◽  
Ring Size ◽  
Flexible Chain ◽  
Photochemical Properties

A series of stiff stilbene macrocycles have been studied to investigate the possible impact of the macrocycle ring size on their photodynamic properties. The results show that reducing the ring size counteracts the photoisomerization ability of the macrocycles. However, even the smallest macrocycle studied (stiff stilbene subunits linked by a six carbon chain) showed some degree of isomerization when irradiated. DFT calculations of the energy differences between the E- and Z-isomers show the same trend as the experimental results. Interestingly the DFT study highlights that the energy difference between the E- and Z-isomers of even the largest macrocycle (linked by a twelve carbon chain) is significantly higher than that of the stiff stilbene unit itself. In general, it is indicated that addition of even a flexible chain to the stiff stilbene unit may significantly affect its photochemical properties and increase the photostability of the resulting macrocycle.

scholarly journals Effect of Ring Size on Photoisomerization Properties of Stiff Stilbene macrocycles

2019 ◽  
Author(s):  
Sandra Olsson ◽  
Óscar Benito Pérez ◽  
Magnus Blom ◽  
Adolf Gogoll
Keyword(s):  
Dft Calculations ◽  
Dynamic Properties ◽  
Energy Difference ◽  
Carbon Chain ◽  
Experimental Results ◽  
Dft Study ◽  
Ring Size ◽  
Flexible Chain ◽  
Photochemical Properties

A series of stiff stilbene macrocycles have been studied to investigate the possible impact of macrocycle ring size on their photo-dynamic properties. The results show that reducing the ring size counteracts the photoisomerization ability of the macrocycles. However, even the smallest macrocycle studied (stiff stilbene subunits linked by a six carbon chain) showed some degree of isomerization when irradiated. DFT calculations of the energy differences between the E- and Z-isomers show the same trend as the experimental results. Interestingly the DFT study highlights that the energy difference between the E- and Z-isomers of even the largest macrocycle (linked by a twelve carbon chain) is significantly higher than that of the stiff stilbene unit itself. In general, it is indicated that addition of even a flexible chain to the stiff stilbene unit may significantly affect  its photochemical properties and increase the photostability of the resulting macrocycle.

Synthetic Route of Trithiolato-Bridged Dinuclear Arene Ruthenium(II) Complexes [(η6-P-MeC6H4Pri)2Ru2(μ2-SR)3]+

2020 ◽  
Author(s):  
Hedvika Primasova ◽  
Silviya Ninova ◽  
Ulrich Aschauer ◽  
julien Furrer ◽  
Mario de Capitani ◽  
...  
Keyword(s):  
Density Functional Theory ◽  
Dft Calculations ◽  
Metal Complexes ◽  
Density Functional ◽  
Ruthenium Complexes ◽  
Experimental Results ◽  
Dft Study ◽  
Synthetic Route ◽  
Functional Theory ◽  
Fundamental Understanding

Several dinuclear thiophenolato-bridged arene ruthenium complexes [(η6-p-MeC6H4Pri)2Ru2(μ2-SC6H4-R)3]+ could so far only<br>be obtained with moderate yields using the synthetic route established in the early 2000s. With much less reactive aliphatic<br>thiols or with bulky thiols, the reactions become even less efficient and the desired complexes are obtained with low yields<br>or not at all. We employed density functional theory (DFT) calculations to gain a fundamental understanding of the reaction<br>mechanisms leading to the formation of dithiolato and trithiolato complexes starting from the dichloro(pcymene)<br>ruthenium(II) dimer [(η6-p-MeC6H4Pri)Ru(μ2-Cl)Cl]2. The results of the DFT study enabled us to rationalise<br>experimental results and allowed us, via a modified synthetic route, to synthesise previously unreported and hitherto<br>considered as unrealistic complexes. Our study opens possibilities for the synthesis of so far inaccessible thiolato-bridged<br>dinuclear arene ruthenium(II) complexes but more generally also the synthesis of other thiolato-bridged dinuclear group 8<br>and 9 metal complexes could be reexamined.

scholarly journals Synthetic Route of Trithiolato-Bridged Dinuclear Arene Ruthenium(II) Complexes [(η6-P-MeC6H4Pri)2Ru2(μ2-SR)3]+

2020 ◽  
Author(s):  
Hedvika Primasova ◽  
Silviya Ninova ◽  
Ulrich Aschauer ◽  
julien Furrer
Keyword(s):  
Density Functional Theory ◽  
Dft Calculations ◽  
Reaction Mechanisms ◽  
Density Functional ◽  
Experimental Results ◽  
Dft Study ◽  
Synthetic Route ◽  
Functional Theory ◽  
Fundamental Understanding ◽  
Aliphatic Thiols

Several dinuclear trithiophenolato-bridged arene ruthenium complexes [(η6-p-MeC6H4Pri)2Ru2(μ2-SC6H4-R)3]+ could so far only be obtained with moderate yields using the synthetic route established in the early 2000s. With much less reactive aliphatic thiols or with bulky thiols, the reactions become even less efficient and the desired trithiolato complexes are obtained either only with bad yields or not at all. We employ density functional theory (DFT) calculations to gain a fundamental understanding of the reaction mechanisms leading to the formation of trithiolato complexes starting from the dichloro(p-cymene)ruthenium(II) dimer [(η6-p-MeC6H4Pri)Ru(μ2-Cl)Cl]2. The results of this DFT study enable us to rationalize experimental results and allow us, via a modified synthetic route, to synthesize the previously unreported and hitherto considered as unrealistic trithiolato complex [(η6-p-MeC6H4Pri)2Ru2(μ2-SC6H11)3]+. Our DFT study opens possibilities for the synthesis of so far inaccessible thiolato-bridged dinuclear arene ruthenium(II) complexes but more generally also the synthesis of other thiolato-bridged dinuclear group 8 and 9 metal com-plexes could be reexamined.

scholarly journals Synthetic Route of Trithiolato-Bridged Dinuclear Arene Ruthenium(II) Complexes [(η6-P-MeC6H4Pri)2Ru2(μ2-SR)3]+

2020 ◽  
Author(s):  
Hedvika Primasova ◽  
Silviya Ninova ◽  
Ulrich Aschauer ◽  
julien Furrer ◽  
Mario de Capitani ◽  
...  
Keyword(s):  
Density Functional Theory ◽  
Dft Calculations ◽  
Metal Complexes ◽  
Density Functional ◽  
Ruthenium Complexes ◽  
Experimental Results ◽  
Dft Study ◽  
Synthetic Route ◽  
Functional Theory ◽  
Fundamental Understanding

Several dinuclear thiophenolato-bridged arene ruthenium complexes [(η6-p-MeC6H4Pri)2Ru2(μ2-SC6H4-R)3]+ could so far only<br>be obtained with moderate yields using the synthetic route established in the early 2000s. With much less reactive aliphatic<br>thiols or with bulky thiols, the reactions become even less efficient and the desired complexes are obtained with low yields<br>or not at all. We employed density functional theory (DFT) calculations to gain a fundamental understanding of the reaction<br>mechanisms leading to the formation of dithiolato and trithiolato complexes starting from the dichloro(pcymene)<br>ruthenium(II) dimer [(η6-p-MeC6H4Pri)Ru(μ2-Cl)Cl]2. The results of the DFT study enabled us to rationalise<br>experimental results and allowed us, via a modified synthetic route, to synthesise previously unreported and hitherto<br>considered as unrealistic complexes. Our study opens possibilities for the synthesis of so far inaccessible thiolato-bridged<br>dinuclear arene ruthenium(II) complexes but more generally also the synthesis of other thiolato-bridged dinuclear group 8<br>and 9 metal complexes could be reexamined.

Mechanistic understanding of the Cu(i)-catalyzed domino reaction constructing 1-aryl-1,2,3-triazole from electron-rich aryl bromide, alkyne, and sodium azide: a DFT study

2021 ◽  
Author(s):  
Hanlin Gan ◽  
Liang Peng ◽  
Feng Long Gu
Keyword(s):  
Density Functional Theory ◽  
Dft Calculations ◽  
Sodium Azide ◽  
Density Functional ◽  
Dft Study ◽  
Domino Reaction ◽  
Aryl Bromide ◽  
Functional Theory ◽  
Mechanistic Understanding

The mechanism of the Cu(i)-catalyzed domino reaction furnishing 1-aryl-1,2,3-triazole assisted by CuI and 1,8-diazabicyclo[5.4.0]undec-7-ene (DBU) is explored with density functional theory (DFT) calculations.

scholarly journals DFT study of superhalogen and superalkali doped graphitic carbon nitride and its non-linear optical properties

RSC Advances ◽  
2021 ◽  
Vol 11 (14) ◽  
pp. 7779-7789 ◽  
Author(s):  
Asmat Ullah Khan ◽  
Rasheed Ahmad Khera ◽  
Naveed Anjum ◽  
Rao Aqil Shehzad ◽  
Saleem Iqbal ◽  
...  
Keyword(s):  
Optical Properties ◽  
Dft Calculations ◽  
Nonlinear Optical ◽  
Carbon Nitride ◽  
Graphitic Carbon ◽  
Graphitic Carbon Nitride ◽  
Dft Study ◽  
Nlo Properties ◽  
Non Linear ◽  
Linear Optical Properties

DFT calculations are carried out to investigate nonlinear optical (NLO) properties of superhalogen (BCl4) and superalkali (NLi4) doped graphitic carbon nitride (GCN).

scholarly journals Density functional theory (DFT) calculations of VI/V reduction potentials of uranyl coordination complexes in non-aqueous solutions

2019 ◽  
Vol 21 (6) ◽  
pp. 3227-3241 ◽  
Author(s):  
Krishnamoorthy Arumugam ◽  
Neil A. Burton
Keyword(s):  
Density Functional Theory ◽  
Dft Calculations ◽  
Aqueous Solutions ◽  
Density Functional ◽  
Coordination Complexes ◽  
Dft Study ◽  
Redox Behavior ◽  
Functional Theory ◽  
Reduction Potentials ◽  
Uranium Complexes

Of particular interest within the +6 uranium complexes is the linear uranyl(vi) cation and it forms numerous coordination complexes in solution and exhibits incongruent redox behavior depending on coordinating ligands. This DFT study predicts VI/V reduction potentials of a range of uranyl(vi) complexes in non-aqueous solutions within ∼0.10−0.20 eV of experiment.

scholarly journals Adsorption of amino acids on MFI-type zeolite: DFT calculations and experimental results

2012 ◽  
Vol 4 (S1) ◽  
Author(s):  
Kai Stueckenschneider ◽  
Achim Zielesny ◽  
Gerhard Schembecker
Keyword(s):  
Amino Acids ◽  
Dft Calculations ◽  
Experimental Results ◽  
Type Zeolite

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.

scholarly journals Generation of 1,2-oxathiolium ions from (arysulfonyl)- and (arylsulfinyl)allenes in Brønsted acids. NMR and DFT study of these cations and their reactions

2018 ◽  
Vol 14 ◽  
pp. 2897-2906 ◽  
Author(s):  
Stanislav V Lozovskiy ◽  
Alexander Yu Ivanov ◽  
Olesya V Khoroshilova ◽  
Aleksander V Vasilyev
Keyword(s):  
Dft Calculations ◽  
Reaction Mechanisms ◽  
Dft Study ◽  
Bronsted Acids ◽  
Allyl Alcohols ◽  
High Yields ◽  
Hydrolysis Of

In strong Brønsted acids (CF3SO3H, FSO3H, D2SO4), (arysulfonyl)allenes (ArSO2–CR1=C=CR2R3) and (arylsulfinyl)allenes (ArSO–CR1=C=CR2R3) undergo cyclization into the corresponding stable 1,2-oxathiolium ions, which were studied by means of NMR and DFT calculations. Quenching of solutions of these cations with low nucleophilic media, aqueous HCl, leads to their deprotonation with a stereoselective formation of (arysulfonyl)butadienes (for instance, ArSO2–CR1=C–C(Me)=CH2, for R2 = R3 = Me, yields of 87–98%). Reactions of (arysulfonyl)allenes in the system TfOH (0.1 equiv)–HFIP (hexafluoropropan-2-ol) followed by hydrolysis give rise to allyl alcohols (ArSO2–CR1=CH–C(OH)R2R3, yields of 78–99%). Reflux of solutions of (arysulfonyl)allenes in the presence of TfOH (1 equiv) in 1,2-dichlorobenzene leads to the cyclization into thiochromene 1,1-dioxides in high yields. Under the action of TfOH or AlX3 (X = Cl, Br) followed by hydrolysis of reaction mixtures, (arylsulfinyl)allenes give allyl alcohols (ArSO2–CR1=CH–C(OH)R2R3). Plausible reaction mechanisms have been proposed for all studied reactions.

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