Ligand substitution and electronic structure studies of bis(phosphine)cobalt cyclooctadiene precatalysts for alkene hydrogenation

Diene self-exchange reactions of the 17-electron, formally cobalt(0) cyclooctadienyl precatalyst, (R,R)-(iPrDuPhos)Co(COD) (P2CoCOD, (R,R)-iPrDuPhos = 1,2-bis((2R,5R)-2,5-diisopropylphospholano)benzene, COD = 1,5-cyclooctadiene) were studied using natural abundance and deuterated 1,5-cyclooctadiene. Exchange of free and coordinated diene was observed at ambient temperature in benzene-d6 solution and kinetic studies support a dissociative process. Both neutral P2CoCOD and the 16-electron, cationic cobalt(I) complex, [(R,R)-(iPrDuPhos)Co(COD)][BArF4] (BArF4 = B[(3,5-(CF3)2)C6H3]4) underwent instantaneous displacement of the 1,5-cyclooctadiene ligand by carbon monoxide and generated the corresponding carbonyl derivatives. The solid-state parameters, DFT-computed Mulliken spin density and analysis of molecular orbitals suggest an alternative description of P2CoCOD as low-spin cobalt(II) with the 1,5-cyclooctadiene acting as a LX2-type ligand. This view of the electronic structure provides insight into the nature of the ligand substitution process and the remarkable stability of the neutral cobalt complexes toward protic solvents observed during catalytic alkene hydrogenation.

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Indirect bandgap, optoelectronic properties, and photoelectrochemical characteristics of high-purity Ta3N5 photoelectrodes

Journal of Materials Chemistry A ◽

10.1039/d1ta05282a ◽

2021 ◽

Vol 9 (36) ◽

pp. 20653-20663

Author(s):

Johanna Eichhorn ◽

Simon P. Lechner ◽

Chang-Ming Jiang ◽

Giulia Folchi Heunecke ◽

Frans Munnik ◽

...

Keyword(s):

Electronic Structure ◽

Electronic Properties ◽

High Purity ◽

Optoelectronic Properties ◽

Precise Control ◽

Insight Into

The (opto)electronic properties of Ta3N5 photoelectrodes are often dominated by defects, but precise control of these defects provides new insight into the electronic structure, photocarrier transport, and photoelectrochemical function.

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Theoretical insight into the effect of Br, Na co-doping on electronic structure, photocatalytic and optical characteristics of g-C3N4 using first-principles and optical simulations

Journal of Materials Science ◽

10.1007/s10853-021-05954-7 ◽

2021 ◽

Author(s):

Zhao-Hui Ruan ◽

Xiu-Yan Gao ◽

Yuan Yuan ◽

He-Ping Tan

Keyword(s):

Electronic Structure ◽

First Principles ◽

Optical Characteristics ◽

Co Doping ◽

Theoretical Insight ◽

Insight Into

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Crystallographic snapshots of ligand binding to hexameric purine nucleoside phosphorylase and kinetic studies give insight into the mechanism of catalysis

Scientific Reports ◽

10.1038/s41598-018-33723-1 ◽

2018 ◽

Vol 8 (1) ◽

Cited By ~ 2

Author(s):

Zoran Štefanić ◽

Marta Narczyk ◽

Goran Mikleušević ◽

Saša Kazazić ◽

Agnieszka Bzowska ◽

...

Keyword(s):

Ligand Binding ◽

Purine Nucleoside Phosphorylase ◽

Kinetic Studies ◽

Purine Nucleoside ◽

Nucleoside Phosphorylase ◽

Mechanism Of Catalysis ◽

Insight Into

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Kinetics of Plasmon-Driven Hydrosilylation of Silicon Surfaces: Photogenerated Charges Drive Silicon- Carbon Bond Formation

10.26434/chemrxiv.14700762 ◽

2021 ◽

Author(s):

Chengcheng Rao ◽

Brian Olsen ◽

Erik Luber ◽

Jillian Buriak

Keyword(s):

Green Light ◽

Kinetic Studies ◽

Silicon Surfaces ◽

Moderate Intensity ◽

Carbon Bond ◽

Silicon Carbon ◽

Set Up ◽

Kinetics Of ◽

Insight Into

Optically transparent PDMS stamps coated with a layer of gold nanoparticles were employed as plasmonic stamps to drive surface chemistry on silicon surfaces. Illumination of a sandwich of plasmonic stamps, an alkene ink, and hydride-terminated silicon with green light of moderate intensity drives hydrosilylation on the surface. The key to the mechanism of the hydrosilylation is the presence of holes at the Si-H-terminated interface, which is followed by attack by a proximal alkene and formation of the silicon-carbon bond. In this work, detailed kinetic studies of the hydrosilylation on silicon with different doping levels, n++, p++, n, p, and intrinsic were carried out to provide further insight into the role of the metal-insulator-semiconductor (MIS) junction that is set up during the stamping.

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Crystal and electronic structure of the new ternary phosphide Ho5Pd19P12

Zeitschrift für Naturforschung B ◽

10.1515/znb-2021-0103 ◽

2021 ◽

Vol 0 (0) ◽

Author(s):

Olha Zhak ◽

Oksana Karychort ◽

Volodymyr Babizhetskyy ◽

Chong Zheng

Keyword(s):

Crystal Structure ◽

Electronic Structure ◽

Quantum Chemical Calculations ◽

Quantum Chemical ◽

Structure Property ◽

X Ray Diffraction ◽

Structure Property Relationships ◽

Metallic Bonding ◽

Crystal And Electronic Structure ◽

Insight Into

Abstract The title compound was prepared from the pure elements by sintering. The crystal structure was investigated by means of powder X-ray diffraction data. Ho5Pd19P12 exhibits the hexagonal Ho5Ni19P12-type structure with space group P 6 ‾ 2 m $P‾{6}2m$ , a = 13.1342(2), c = 3.9839(1) Å, R I = 0.060, R p = 0.080. The crystal structure can be described as a combination of two types of the structural units, [HoPd6P3] and [Ho3Pd10P6], respectively, mutually displaced by 1/2 along the crystallographic c axis. Quantum chemical calculations have been performed to analyze the electronic structure and provide deeper insight into the structure-property relationships. The results of the quantum chemical calculations indicate that the material features metallic bonding between Ho and Pd and covalent bonding between Pd and P.

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