Electronic effects in C-H and C-C bond activation. State-specific reactions of FE+ (6D,4F) with methane, ethane, and propane

1988 ◽  
Vol 110 (2) ◽  
pp. 411-423 ◽  
Author(s):  
Richard H. Schultz ◽  
J. L. Elkind ◽  
P. B. Armentrout
Keyword(s):  
Bond Activation ◽  
Electronic Effects ◽  
Specific Reactions

The oxidative coupling between benzaldehyde derivatives and phenylacetylene catalyzed by rhodium complexes via C-H bond activation

2020 ◽  
Vol 26 (1) ◽  
pp. 20-25
Author(s):  
Xinyi Zhao ◽  
Hongge Jia ◽  
Qingji Wang ◽  
Heming Song ◽  
Yanan Tang ◽  
...  
Keyword(s):  
Amino Acid ◽  
Oxidative Coupling ◽  
Bond Activation ◽  
Coupling Reaction ◽  
Reaction Yield ◽  
Rhodium Complexes ◽  
Electronic Effects ◽  
Oxidative Coupling Reaction ◽  
Excellent Activity ◽  
Benzaldehyde Derivatives

AbstractThis paper reports the use of rhodium (Rh) catalysts for the oxidative coupling reaction between phenylacetylene and benzaldehyde derivatives via C-H bond activation. These reactions were catalyzed by Rh(l-amino acid)(cod) (the l-amino acid is l-phenylalanine, l-valine or l-proline; cod is 1,5-cyclooctadiene) to obtain chromones in 12.7–88.3% yield. These new Rh catalysts have excellent activity for the coupling reaction between phenylacetylene and different benzaldehyde derivatives. It was found that the electronic effects of the benzaldehyde derivative substituent affected the reaction yield, which is in accordance with the proposed mechanism.

State-Specific Reactions of Cu+(1S,3D) with CH3X and CF3X (X = Cl, Br, I): Exploring the Influence of Dipole Orientation on Association and C–X Bond Activation

2012 ◽  
Vol 116 (16) ◽  
pp. 3979-3988 ◽  
Author(s):  
William S. Taylor ◽  
Micah L. Abrams ◽  
Cullen C. Matthews ◽  
Seth Byers ◽  
Scott Musial ◽  
...  
Keyword(s):  
Bond Activation ◽  
Dipole Orientation ◽  
Specific Reactions

Steric and Electronic Effects Influencing β-Aryl Elimination in the Pd-catalyzed Carbon–Carbon Single Bond Activation of Triarylmethanols

2013 ◽  
Vol 78 (4) ◽  
pp. 1665-1669 ◽  
Author(s):  
James R. Bour ◽  
Jacob C. Green ◽  
Valerie J. Winton ◽  
Jeffrey B. Johnson
Keyword(s):  
Bond Activation ◽  
Single Bond ◽  
Electronic Effects

Significant hydrogen-bonding effect on the reactivity of high-valent manganese(V)–oxo porphyrins in C–H bond activation: A DFT study

2015 ◽  
Vol 19 (11) ◽  
pp. 1197-1203 ◽  
Author(s):  
Abdolreza Rezaeifard ◽  
Hossein Kavousi ◽  
Heidar Raissi ◽  
Maasoumeh Jafarpour
Keyword(s):  
Hydrogen Bonding ◽  
Bond Activation ◽  
Nbo Analysis ◽  
Electronic Effects ◽  
Unusual Behavior ◽  
Aim Analysis ◽  
Oxidation Activity ◽  
Bonding Effect ◽  
Phenyl Rings ◽  
High Valent

The stereo electronic effects as well as hydrogen bonding effects of imidazole, pyridine and 2,6-dimethylpyridine as N-donor axial ligands on the C–H oxidation activity of high-valent manganese(V)–oxo meso-tetraphenylporphyrin (TPP) and meso-tetrakis(pentaflourophenyl)porphyrin (TPFPP), are investigated by DFT calculations. The electronic and steric properties of axial donors and porphyrin ligands affected on the activation energy of cyclohexane hydroxylation as well as the Mn–O bond strength of the oxo species in transition state. Imidazole with the strong [Formula: see text]-donating ability and the least steric hindrance showed greater co-catalytic activity than those of pyridine and in particularly hindered 2,6-Me2 pyridine in the presence of simple [(TPP)MnO][Formula: see text]. Nevertheless, the C–H bond activation by hindered and electron-deficient perfluorinated catalyst [(TPFPP)MnO][Formula: see text] is in the order of pyridine >2, 6-Me2 pyridine >imidazole. AIM analysis showed hydrogen bonding (HB) between the C–H [Formula: see text] bonds of pyridine (C[Formula: see text]-H of ring) and 2,6-Me2Py (C[Formula: see text]-H of methyl groups) with ortho-C–F bond of phenyl rings of TPFPP in Mn[Formula: see text]O species (C–H…..F–C hydrogen bond) which might be responsible for this unusual behavior. These results are supported by natural bond orbital (NBO) analysis.

DFT modelling of a diphosphane − N-heterocyclic carbene–Rh(i) pincer complex rearrangement: a computational evaluation of the electronic effects in C–P bond activation

2018 ◽  
Vol 47 (8) ◽  
pp. 2662-2669 ◽  
Author(s):  
H.-L. Qin ◽  
J. Leng ◽  
W. Zhang ◽  
E. A. B. Kantchev
Keyword(s):  
Dft Calculations ◽  
Bond Activation ◽  
Oxidative Addition ◽  
Reductive Elimination ◽  
Electronic Effects ◽  
Complex Rearrangement ◽  
Rate Determining Step ◽  
Computational Evaluation ◽  
Pincer Complex ◽  
Dft Modelling

DFT calculations confirmed that the rearrangement of a PCP-Rh-H pincer to a CCP-Rh-phosphane pincer occured by C–P oxidative addition (ΔG‡ = 29.5 kcal mol−1, rate-determining step), followed by P–H reductive elimination (ΔG‡ = 4.8 kcal mol−1).

Differences in the Way to Conceive Happiness Relate to Different Reactions to Negative Events

2018 ◽  
Vol 39 (1) ◽  
pp. 27-38 ◽  
Author(s):  
Giulia Fuochi ◽  
Chiara A. Veneziani ◽  
Alberto Voci
Keyword(s):  
Positive Emotions ◽  
Satisfaction With Life ◽  
Well Being ◽  
Protective Role ◽  
Stressful Events ◽  
Interactive Effects ◽  
Negative Events ◽  
Orientations To Happiness ◽  
Specific Reactions ◽  
The Way

Abstract. This paper aimed to assess whether differences in the way to conceive happiness, measured by the Orientations to Happiness measure, were associated with specific reactions to negative events. We hypothesized that among orientations to pleasure (portraying hedonism), to meaning (representing a eudaimonic approach to life), and to engagement (derived from the experience of flow), orientation to meaning would have displayed a stronger protective role against recent negative and potentially stressful events. After providing a validation of the Italian version of the Orientations to Happiness measure (Study 1), we performed regression analyses of the three orientations on positive and negative emotions linked to a self-relevant negative event (Study 2), and moderation analyses assessing the interactive effects of orientations to happiness and stressful events on well-being indicators (Study 3). Our findings supported the hypotheses. In Study 2, meaning was associated with positive emotions characterized by a lower activation (contentment and interest) compared to the positive emotions associated with pleasure (amusement, eagerness, and happiness). In Study 3, only meaning buffered the effect of recent potentially stressful events on satisfaction with life and positive affect. Results suggest that orientation to meaning might help individuals to better react to negative events.

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