scholarly journals Application of Natural Orbital Fukui Functions and Bonding Reactivity Descriptor in Understanding Bond Formation Mechanisms Underlying [2+4] and [4+2] Cycloadditions of o-Thioquinones with 1, 3-Dienes

2018 ◽  
Vol 34 (5) ◽  
pp. 497-502 ◽  
Author(s):  
Chaoxian YAN ◽  
◽  
Fan YANG ◽  
Ruizhi WU ◽  
Dagang ZHOU ◽  
...  
Keyword(s):  
Bond Formation ◽  
Formation Mechanisms ◽  
Natural Orbital ◽  
Fukui Functions ◽  
Reactivity Descriptor

scholarly journals From Ru-bda to Ru-bds: a step forward to highly efficient molecular water oxidation electrocatalysts under acidic and neutral conditions

2021 ◽  
Vol 12 (1) ◽  
Author(s):  
Jing Yang ◽  
Lei Wang ◽  
Shaoqi Zhan ◽  
Haiyuan Zou ◽  
Hong Chen ◽  
...  
Keyword(s):  
Water Oxidation ◽  
Density Functional ◽  
Bond Formation ◽  
Density Functional Theory Calculations ◽  
Oxidation Catalyst ◽  
Nucleophilic Attack ◽  
Molecular Water ◽  
Formation Mechanisms ◽  
Equatorial Position ◽  
Neutral Conditions

AbstractSignificant advances during the past decades in the design and studies of Ru complexes with polypyridine ligands have led to the great development of molecular water oxidation catalysts and understanding on the O−O bond formation mechanisms. Here we report a Ru-based molecular water oxidation catalyst [Ru(bds)(pic)2] (Ru-bds; bds2− = 2,2′-bipyridine-6,6′-disulfonate) containing a tetradentate, dianionic sulfonate ligand at the equatorial position and two 4-picoline ligands at the axial positions. This Ru-bds catalyst electrochemically catalyzes water oxidation with turnover frequencies (TOF) of 160 and 12,900 s−1 under acidic and neutral conditions respectively, showing much better performance than the state-of-art Ru-bda catalyst. Density functional theory calculations reveal that (i) under acidic conditions, the high valent Ru intermediate RuV=O featuring the 7-coordination configuration is involved in the O−O bond formation step; (ii) under neutral conditions, the seven-coordinate RuIV=O triggers the O−O bond formation; (iii) in both cases, the I2M (interaction of two M−O units) pathway is dominant over the WNA (water nucleophilic attack) pathway.

Formation of C–C bonds during electrocatalytic CO2 reduction on non-copper electrodes

2020 ◽  
Vol 8 (44) ◽  
pp. 23162-23186
Author(s):  
Yansong Zhou ◽  
Boon Siang Yeo
Keyword(s):  
Electrochemical Reduction ◽  
Bond Formation ◽  
Co2 Reduction ◽  
Formation Mechanisms ◽  
Copper Electrodes ◽  
Recent Advances ◽  
Cu Catalysts

Recent advances in non-Cu catalysts for electrochemical reduction of CO2 to multi-carbon products are summarized, focusing on C–C bond formation mechanisms.

Kinetic studies on cyclopalladation in palladium(II) complexes containing an indole moiety

2014 ◽  
Vol 86 (2) ◽  
pp. 151-161 ◽  
Author(s):  
Satoshi Iwatsuki ◽  
Takuya Suzuki ◽  
Syogo Tanooka ◽  
Tatsuo Yajima ◽  
Yuichi Shimazaki
Keyword(s):  
Bond Formation ◽  
Kinetic Studies ◽  
Catalytic Reactions ◽  
Biological Molecules ◽  
Side Chain ◽  
Formation Mechanisms ◽  
Indole Derivatives ◽  
Reaction Intermediates ◽  
Pd Catalysts ◽  
Amino Acid Tryptophan

Abstract Various Pd–C complexes have been developed to date, affording deep insights into the reaction intermediates in useful catalytic reactions in organic syntheses. Cyclopalladation is one of the most famous Pd–C bond formation reactions to generate the palladacycles. Indole is an electron-rich aromatic ring involved in the side chain of an essential amino acid, tryptophan (Trp), and Trp and its derivatives are important in biological systems, such as electron transfer in protein, cofactors for conversion of biological molecules and so on. Pd catalysts are also useful for syntheses of such indole derivatives, and the mechanisms are considered to be through the Pd–C intermediates. However, the detailed properties and formation mechanisms of Pd–indole species are still unclear. With these points in mind, we focus on Pd(II)–indole-C2 carbon bond formations using various Pd(II) complexes having an indole moiety, especially on the recent studies on the kinetic analyses for these cyclopalladation reactions and their detailed mechanisms.

scholarly journals O–O bond formation mechanisms during the oxygen evolution reaction over synthetic molecular catalysts

2021 ◽  
Vol 42 (8) ◽  
pp. 1253-1268
Author(s):  
Xue-Peng Zhang ◽  
Hong-Yan Wang ◽  
Haoquan Zheng ◽  
Wei Zhang ◽  
Rui Cao
Keyword(s):  
Oxygen Evolution ◽  
Oxygen Evolution Reaction ◽  
Bond Formation ◽  
Formation Mechanisms ◽  
Molecular Catalysts

Role of Solvent on Nonenzymatic Peptide Bond Formation Mechanisms and Kinetic Isotope Effects

2013 ◽  
Vol 135 (23) ◽  
pp. 8708-8719 ◽  
Author(s):  
Katarzyna Świderek ◽  
Iñaki Tuñón ◽  
Sergio Martí ◽  
Vicent Moliner ◽  
Juan Bertrán
Keyword(s):  
Isotope Effects ◽  
Bond Formation ◽  
Peptide Bond ◽  
Kinetic Isotope Effects ◽  
Formation Mechanisms ◽  
Peptide Bond Formation ◽  
Kinetic Isotope ◽  
Role Of Solvent

scholarly journals Studies on the C-P Bond Formation Mechanisms in Bialaphos.

1992 ◽  
Vol 6 (2) ◽  
pp. 105-112
Author(s):  
Tomomi Hidaka ◽  
Haruo Seto
Keyword(s):  
Bond Formation ◽  
Formation Mechanisms

The dislocation structure of a 10° [110] tilt boundary in silicon

1983 ◽  
Vol 41 ◽  
pp. 114-115
Author(s):  
B. Cunningham ◽  
D.G. Ast
Keyword(s):  
Dislocation Structure ◽  
Tilt Angle ◽  
Imaging Technique ◽  
Diamond Lattice ◽  
Tilt Boundary ◽  
Formation Mechanisms ◽  
Diffraction Contrast ◽  
Lattice Fringe ◽  
Tilt Boundaries ◽  
Chemically Vapor Deposited

There have Been a number of studies of low-angle, θ < 4°, [10] tilt boundaries in the diamond lattice. Dislocations with Burgers vectors a/2<110>, a/2<112>, a<111> and a<001> have been reported in melt-grown bicrystals of germanium, and dislocations with Burgers vectors a<001> and a/2<112> have been reported in hot-pressed bicrystals of silicon. Most of the dislocations were found to be dissociated, the dissociation widths being dependent on the tilt angle. Possible dissociation schemes and formation mechanisms for the a<001> and a<111> dislocations from the interaction of lattice dislocations have recently been given.The present study reports on the dislocation structure of a 10° [10] tilt boundary in chemically vapor deposited silicon. The dislocations in the boundary were spaced about 1-3nm apart, making them difficult to resolve by conventional diffraction contrast techniques. The dislocation structure was therefore studied by the lattice-fringe imaging technique.

Formation Mechanisms for Multiply Twinned Particles During Nucleation in the Au/MICA System

1975 ◽  
Vol 33 ◽  
pp. 84-85
Author(s):  
Eal H. Lee ◽  
Helmut Poppa
Keyword(s):  
Deposition Time ◽  
High Vacuum ◽  
Dark Field ◽  
Ultra High Vacuum ◽  
Formation Mechanisms ◽  
Heat Treated ◽  
Cluster Density ◽  
Diffraction Patterns ◽  
Crystal Particle ◽  
Multiply Twinned Particles

The formation of thin films of gold on mica has been studied in ultra-high vacuum (5xl0-10 torr) . The mica substrates were heat-treated for 24 hours at 375°C, cleaved, and annealed for 15 minutes at the deposition temperature of 300°C prior to deposition. An impingement flux of 3x1013 atoms cm-2 sec-1 was used. These conditions were found to give high number densities of multiple twin particles and are based on a systematic series of nucleation experiments described elsewhere. Individual deposits of varying deposition time were made and examined by bright and dark field TEM after "cleavage preparation" of highly transparent specimens. In the early stages of growth, the films generally consist of small particles which are either single crystals or multiply twinned; a strong preference for multiply twinned particles was found whenever the particle number densities were high. Fig. 1 shows the stable cluster density ns and the variation with deposition time of multiple twin particle and single crystal particle densities, respectively. Corresponding micrographs and diffraction patterns are shown in Fig. 2.

Sign in / Sign up

Export Citation Format

Share Document