Pt(II) Derivatives with Rollover-Coordinated 6-substituted 2,2′-bipyridines: Ligands with Multiple Personalities

We report here the synthesis, characterization and behavior of a series of Pt(II) cyclometalated rollover complexes with two substituted bipyridines, 6-ethyl-2,2′-bipyridine (bpy6Et) and 6-methoxy-2,2′-bipyridine (bpy6OMe), in comparison with previously studied 2,2′-bipyridine complexes. The two ligands have similar steric hindrance but different electronic properties. As a result, the reactivity of the two series of complexes follows very different routes. In particular, the new complexes behave differently towards protonation reactions, differences given by substituents and ancillary ligands, added to the presence of several nucleophilic centers. Reaction of complex [Pt(bpy6OMe-H)(PPh3)Me)] with [H3O⋅18-crown-6][BF4] results in a retro-rollover reaction whose final product is the cationic adduct [Pt(bpy6OMe)(PPh3)Me)]+. Surprisingly, only the isomer with the cis-PPh3-OMe geometry is formed; in spite of an expected instability due to steric hindrance, Density-Functional theory (DFT) calculations showed that this isomer is the most stable. This result shows that the cone angle is far from being a real “solid cone” and should lead to a different interpretation of well-known concepts concerning steric bulk of ligands, such as cone angle. Proton affinity values of ligands, neutral complexes and their protonated counterparts were analyzed by means of DFT calculations, allowing a comparison of their properties.

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Study of the Molecular Properties of Mono- and Binuclear Metal s-Indacenyl Complexes with Ir, Rh, and Re: A Theoretical Approach

Journal of Chemistry ◽

10.1155/2017/9101720 ◽

2017 ◽

Vol 2017 ◽

pp. 1-8

Author(s):

Ximena Zarate ◽

Eduardo Schott ◽

Emilio Bunel ◽

Juan M. Manríquez ◽

Ivonne Chávez

Keyword(s):

Density Functional Theory ◽

Dft Calculations ◽

Electronic Properties ◽

Density Functional ◽

Functional Theory ◽

Ancillary Ligands ◽

Bridging Ligand ◽

New Family ◽

Reactivity Indexes ◽

Binuclear Metal

Density functional theory (DFT) calculations were performed on a new family of mono- and bimetallic complexes, containing 4,8-([10]paracyclophane)-1,5-dihydro-s-indacene as the bridging ligand between the two metallic centers and different ancillary ligands. The s-indacene was blocked by substitution of the central benzene ring with the [10]paracyclophane to obtain the syn-conformations. This would force the metallic centers to be close together. It is proposed, due to the calculated molecular and electronic properties such as the reactivity indexes, the delocalized nature of the s-indacenyl ligand, and the electron-rich metals, that these systems could be reactive in a catalytic reaction. The results indicate that the systems with Rh and Re holding ancillary ligands such as bipy and CO show the best properties to be active in a chemical reaction. In this sense, by the assessed geometrical and electronic properties, when compared with a previously reported system, these complexes could be candidates for the reduction of CO2 to oxalate.

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γ-Valerolactone-Introduced Controlled-Isomerization of Glucose for Lactic Acid Production over Sn-Beta Catalyst

Green Chemistry ◽

10.1039/d1gc00378j ◽

2021 ◽

Author(s):

Xinpeng Zhao ◽

Zhimin Zhou ◽

hu luo ◽

Yanfei Zhang ◽

Wang Liu ◽

...

Keyword(s):

Density Functional Theory ◽

Lactic Acid ◽

Dft Calculations ◽

Acid Production ◽

Density Functional ◽

Lactic Acid Production ◽

Hydrothermal Conversion ◽

Functional Theory ◽

Environment Friendly

Combined experiments and density functional theory (DFT) calculations provided insights into the role of the environment-friendly γ-valerolactone (GVL) as a solvent in the hydrothermal conversion of glucose into lactic acid...

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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

Catalysis Science & Technology ◽

10.1039/d1cy00123j ◽

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.

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Graph theory-based reaction pathway searches and DFT calculations for the mechanism studies of free radical-initiated peptide sequencing mass spectrometry (FRIPS MS): a model gas-phase reaction of GGR tri-peptide

Physical Chemistry Chemical Physics ◽

10.1039/c9cp05433b ◽

2020 ◽

Vol 22 (9) ◽

pp. 5057-5069 ◽

Cited By ~ 1

Author(s):

Jae-ung Lee ◽

Yeonjoon Kim ◽

Woo Youn Kim ◽

Han Bin Oh

Keyword(s):

Graph Theory ◽

Dft Calculations ◽

Gas Phase ◽

Density Functional ◽

Reaction Pathway ◽

Peptide Sequencing ◽

Phase Reaction ◽

Functional Theory ◽

Fragmentation Mechanisms ◽

Gas Phase Fragmentation

A new approach for elucidating gas-phase fragmentation mechanisms is proposed: graph theory-based reaction pathway searches (ACE-Reaction program) and density functional theory (DFT) calculations.

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

Physical Chemistry Chemical Physics ◽

10.1039/c8cp05412f ◽

2019 ◽

Vol 21 (6) ◽

pp. 3227-3241 ◽

Cited By ~ 1

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.

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Iron(II) complexes of dimethyltriazacyclophane

Acta Crystallographica Section C Structural Chemistry ◽

10.1107/s2053229618015255 ◽

2018 ◽

Vol 74 (12) ◽

pp. 1641-1649

Author(s):

Wei-Tsung Lee ◽

Matthias Zeller ◽

David Upp ◽

Yuliya Politanska ◽

Doug Steinman ◽

...

Keyword(s):

Density Functional Theory ◽

Solid State ◽

Dft Calculations ◽

Density Functional Calculations ◽

Density Functional ◽

Coordination Mode ◽

Functional Theory ◽

Metal Centers ◽

Bonding Interaction

Treatment of the ortho-triazacyclophane 1,4-dimethyltribenzo[b,e,h][1,4,7]triazacyclonona-2,5,8-triene [(C6H5)3(NH)(NCH3)2, L1] with Fe[N(SiMe3)2]2 yields the dimeric iron(II) complex bis(μ-1,4-dimethyltribenzo[b,e,h][1,4,7]triazacyclonona-2,5,8-trien-7-ido)bis[(μ-1,4-dimethyltribenzo[b,e,h][1,4,7]triazacyclonona-2,5,8-trien-7-ido)iron(II)], [Fe(C20H18N3)4] or Fe2(L1)4 (9). Dissolution of 9 in tetrahydrofuran (THF) results in solvation by two THF ligands and the formation of a simpler monoiron complex, namely bis(μ-1,4-dimethyltribenzo[b,e,h][1,4,7]triazacyclonona-2,5,8-trien-7-ido-κN 7)bis(tetrahydrofuran-κO)iron(II), [Fe(C20H18N3)2(C4H8O)2] or (L1)2Fe(THF)2 (10). The reaction is reversible and 10 reverts in vacuo to diiron complex 9. In the structures of both 9 and 10, the monoanionic triazacyclophane ligand L1− is observed in only the less-symmetric saddle conformation. No bowl-shaped crown conformers are observed in the solid state, thus preventing chelating κ3-coordination to the metal as had been proposed earlier based on density functional theory (DFT) calculations. Instead, the L1− ligands are bound in either a η2-chelating fashion through the amide and one amine donor (for one of the four ligands of 9), or solely through their amide N atoms in an even simpler monodentate η1-coordination mode. Density functional calculations on dimer 9 revealed nearly full cationic charges on each Fe atom and no bonding interaction between the two metal centers, consistent with the relatively long Fe...Fe distance of 2.912 (1) Å observed in the solid state.

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Synthesis, characterization, crystal structure and density functional theory (DFT) calculations of dioxomolybdenum (VI) complexes of an ONS donor ligand derived from benzoylacetone and S-benzyl dithiocarbazate

Polyhedron ◽

10.1016/j.poly.2012.12.006 ◽

2013 ◽

Vol 50 (1) ◽

pp. 602-611 ◽

Cited By ~ 9

Author(s):

Manashi Chakraborty ◽

Sathi Roychowdhury ◽

Nikhil Ranjan Pramanik ◽

Tapas Kumar Raychaudhuri ◽

Tapan Kumar Mondal ◽

...

Keyword(s):

Crystal Structure ◽

Density Functional Theory ◽

Dft Calculations ◽

Density Functional ◽

Functional Theory ◽

Donor Ligand

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The Pivotal Alkyne Group in the Mutual Size-Conversion of Au9 with Au10 Nanoclusters

Dalton Transactions ◽

10.1039/d1dt01586a ◽

2021 ◽

Author(s):

Xiaohang Wu ◽

Ying Lv ◽

Yuyuan Bai ◽

Haizhu Yu ◽

Manzhou Zhu

Keyword(s):

Density Functional Theory ◽

Theoretical Model ◽

Dft Calculations ◽

Density Functional ◽

Single Atom ◽

Functional Theory

Herein, density functional theory (DFT) calculations were performed to elucidate the mechanism of the reversible single atom size conversion between [Au10(DMPP)4(C6H11C≡C)]3+ and [Au9(DMPP)4]3+ (DMPP is 2,2’-bis-(dimethylphosphino)-1,1’-biphenyl, the simplified, theoretical model...

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Design and Prediction of High Potent ansa-Zirconocene for Olefin Polymerizations: Combined DFT Calculations and QSPR Approach

New Journal of Chemistry ◽

10.1039/d1nj00655j ◽

2021 ◽

Author(s):

Manussada Ratanasak ◽

Jun-ya Hasegawa ◽

Vudhichai Parasuk

Keyword(s):

Density Functional Theory ◽

Dft Calculations ◽

Density Functional ◽

Functional Theory ◽

Olefin Polymerizations

Homopolymerization of ethene (ET), propene (PP), 1-butene (BT), 1-hexene (HX), and styrene (ST) by rac [Zr{1-Me2Si(3-Pr-(η5-C9H5))(3-H-(η5-C9H5))Cl2] ansa-zirconocene catalyst were investigated using Density Functional Theory (DFT) calculations. This study unveiled the...

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Iron Chelation by thiocytosine: Investigating electronic and structural features for describing tautomerism and metal chelation processes

Main Group Chemistry ◽

10.3233/mgc-210110 ◽

2021 ◽

pp. 1-8

Author(s):

Azadeh Jafari Rad ◽

Maryam Abbasi ◽

Bahareh Zohrevand

Keyword(s):

Density Functional Theory ◽

Dft Calculations ◽

Molecular Orbital ◽

Density Functional ◽

Biological Systems ◽

Iron Chelation ◽

Structural Features ◽

Metal Chelation ◽

Functional Theory

This work was performed regarding the importance of iron (Fe) chelation for biological systems. This goal was investigated by assistance of a model of thiocytosine (TC) for participating in Fe-chelation processes. First, formations of tautomeric conformations were investigated to explore existence of possible structures of TC. Next, Fe-chelation processes were examined for all four obtained tautomers of TC. The results indicated that thiol tautomers could be seen at higher stability than thio tautomers, in which one of such thiol tautomers yielded the strongest Fe-chelation process to build FeTC3 model. As a consequence, parallel to the results of original TC tautomers, Fe-chelated models were found to be achievable for meaningful chelation processes or sensing the existence of Fe in media. Examining molecular orbital features could help for sensing purposes. The results of this work were obtained by performing density functional theory (DFT) calculations proposing TC compounds suitable for Fe-chelation purposes.

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