Unprecedented η3-Coordination and Functionalization of the 2-Phosphaethynthiolate Anion at Lanthanum(III)

We present the unprecedented η3-coordination of the 2-phosphaethynthiolate anion in the complex (PN)2La(SCP) (2) [PN = N-(2-(diisopropylphosphanyl)-4-methylphenyl)-2,4,6-trimethylanilide)]. Structural comparison with dinuclear thiocyanate bridged (PN)2La(μ-1,3-SCN)2La(PN)2 (3) and azide bridged (PN)2La(μ-1,3-N3)2La(PN)2 (4) complexes indicates that the [SCP]– coordination mode is mainly governed by electronic, rather than steric factors. Quantum mechanical investigations reveal large contributions of the antibonding π-orbital of the [SCP]– ligand to the LUMO of complex 2, rendering it the ideal precursor for the first functionalization of the [SCP]– anion. Complex 2 was therefore reacted with CAACs which induced a selective rearrangement of the [SCP]– ligand to form the first CAAC stabilized group 15 – group 16 fulminate-type complexes (PN)2La{SPC(RCAAC)} (5a,b) (R = Ad, Me). A detailed reaction mechanism for the SCP to SPC isomerization is proposed based on DFT calculations.

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Catalytic polymerization of naphthalene by HF/BF3 super acid: an ab initio density functional theory study

Physical Chemistry Chemical Physics ◽

10.1039/c8cp02777c ◽

2018 ◽

Vol 20 (36) ◽

pp. 23311-23319 ◽

Cited By ~ 1

Author(s):

Po-Yu Yang ◽

Hsing-Yin Chen ◽

Shin-Pon Ju ◽

Chia-Lin Chang ◽

Gao-Shee Leu ◽

...

Keyword(s):

Density Functional Theory ◽

Reaction Mechanism ◽

Dft Calculations ◽

Ab Initio ◽

Density Functional ◽

Catalytic Polymerization ◽

Density Functional Theory Study ◽

Functional Theory ◽

Detailed Reaction Mechanism ◽

Super Acid

The detailed reaction mechanism of naphthalene catalytic polymerization by HF/BF3 has been investigated by DFT calculations and the directionality of the naphthalene-derived mesophase molecule has been explained.

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Mechanism, selectivity, and reactivity of iridium- and rhodium-catalyzed intermolecular ketone α-alkylation with unactivated olefinsviaan enamide directing strategy

Catalysis Science & Technology ◽

10.1039/c8cy00290h ◽

2018 ◽

Vol 8 (9) ◽

pp. 2417-2426 ◽

Cited By ~ 15

Author(s):

Xiaojie Li ◽

Hongli Wu ◽

Yanmin Lang ◽

Genping Huang

Keyword(s):

Reaction Mechanism ◽

Dft Calculations ◽

Title Reaction ◽

Detailed Reaction Mechanism

DFT calculations were performed to investigate the title reaction, focusing on detailed reaction mechanism and origins of selectivity and reactivity.

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Reactions of an Aluminium(I) Reagent with 1,2-, 1,3- and 1,5-Dienes: Dearomatisation, Reversibility, and a Pericyclic Mechanism

10.26434/chemrxiv.11400171.v1 ◽

2019 ◽

Author(s):

Clare Bakewell ◽

Martí Garçon ◽

Richard Y Kong ◽

Louisa O'Hare ◽

Andrew J. P. White ◽

...

Keyword(s):

Reaction Mechanism ◽

Dft Calculations ◽

Transition State ◽

Reaction Pathways ◽

Aromatic Rings ◽

Aromatic Character ◽

Pericyclic Reaction

The reactions of an aluminium(I) reagent with a series of 1,2-, 1,3- and 1,5-dienes are reported. In the case of 1,3-dienes the reaction occurs by a pericyclic reaction mechanism, specifically a cheletropic cycloaddition, to form aluminocyclopentene containing products. This mechanism has been interrogated by stereochemical experiments and DFT calculations. The stereochemical experiments show that the (4+1) cycloaddition follows a suprafacial topology, while calculations support a concerted albeit asynchronous pathway in which the transition state demonstrates aromatic character. Remarkably, the substrate scope of the (4+1) cycloaddition includes dienes that are either in part, or entirely, contained within aromatic rings. In these cases, reactions occur with dearomatisation of the substrate and can be reversible. In the case of 1,2- or 1,5-dienes complementary reactivity is observed; the orthogonal nature of the C=C π-bonds (1,2-diene) and the homoconjugated system (1,5-diene) both disfavour a (4+1) cycloaddition. Rather, reaction pathways are determined by an initial (2+1) cycloaddition to form an aluminocyclopropane intermediate which can in turn undergo insertion of a further C=C π-bond leading to complex organometallic products that incorporate fused hydrocarbon rings.

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Catalytic mechanism of the colistin resistance protein MCR-1

Organic & Biomolecular Chemistry ◽

10.1039/d0ob02566f ◽

2021 ◽

Author(s):

Reynier Suardíaz ◽

Emily Lythell ◽

Philip Hinchliffe ◽

Marc van der Kamp ◽

James Spencer ◽

...

Keyword(s):

Reaction Mechanism ◽

Antimicrobial Resistance ◽

Dft Calculations ◽

Catalytic Reaction ◽

Catalytic Mechanism ◽

Cluster Models ◽

Colistin Resistance ◽

Resistance Protein ◽

Catalytic Reaction Mechanism

Elucidation of the catalytic reaction mechanism of MCR-1 enzyme, responsible for the antimicrobial resistance to colistin, using DFT calculations on cluster models.

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Protein-ligand free energies of binding from full-protein DFT calculations: convergence and choice of exchange-correlation functional

Physical Chemistry Chemical Physics ◽

10.1039/d1cp00206f ◽

2021 ◽

Author(s):

Lennart Gundelach ◽

Christofer S Tautermann ◽

Thomas Fox ◽

Chris-Kriton Skylaris

Keyword(s):

Drug Discovery ◽

Ligand Binding ◽

Dft Calculations ◽

Quantum Mechanical ◽

Free Energies ◽

Ligand Interaction ◽

Exchange Correlation ◽

Ligand Free ◽

Protein Ligand Interaction ◽

Binding Free Energies

The accurate prediction of protein-ligand binding free energies with tractable computational methods has the potential to revolutionize drug discovery. Modeling the protein-ligand interaction at a quantum mechanical level, instead of...

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A detailed reaction mechanism for elemental sulphur combustion in the furnace of sulphuric acid plants

The Canadian Journal of Chemical Engineering ◽

10.1002/cjce.24185 ◽

2021 ◽

Author(s):

Najah Mahmoud Abumounshar ◽

Salisu Ibrahim ◽

Abhijeet Raj

Keyword(s):

Reaction Mechanism ◽

Sulphuric Acid ◽

Elemental Sulphur ◽

Detailed Reaction Mechanism

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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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