Results 311 to 320 of about 11,627,235 (359)

Remote Control by Steric Effects

Science, 2014
A rhodium-catalyzed reaction places a silicon substituent on the site farthest away from the largest group present on an aromatic ring. [Also see Research Article by Cheng and Hartwig ]
Naoto Chatani, Mamoru Tobisu
openaire   +2 more sources

Fisher information and steric effect

Chemical Physics Letters, 2007
Abstract A modified Fisher information, the sum of the one-electron Fisher information, is proposed. It is shown that the modified Fisher information is the original Fisher information plus a sum of differences of quantum and classical variances. A generalization of the Stam’s inequality is derived.
openaire   +2 more sources

Steric effects in carbene cycloadditions

Tetrahedron Letters, 1983
Abstract Steric effects in cycloadditions with alkenes prevent the occurrence of a general linear free energy relationship between the reactivities of carbenes. Nevertheless, the isoselective temperature remains constant.
Bernd Giese, Woo Bung Lee, Carola Stiehl
openaire   +2 more sources

Regularized regression analysis of digitized molecular structures in organic reactions for quantification of steric effects

Journal of Computational Chemistry, 2017
In organic chemistry, Comparative Molecular Field Analysis (CoMFA) can be defined as a regression analysis between reaction outcomes and molecular fields, wherein we can extract and visualize important structural information from the coefficients of the ...
S. Yamaguchi, T. Nishimura, Yuta Hibe, Masaki Nagai, Hirofumi Sato, Ian Johnston   +5 more
semanticscholar   +1 more source

The Role of Steric Effects and Acidity in the Direct Synthesis of iso‐Paraffins from Syngas on Cobalt Zeolite Catalysts

, 2016
This study focuses on the effects of the localization of Co species, zeolite structure, and acidity on the performance of Co bifunctional catalysts promoted with Pt for the direct synthesis of iso‐paraffins from syngas. ZSM‐5, MOR, and BEA were chosen as
V. Subramanian, V. Zholobenko, K. Cheng, C. Lancelot, S. Heyte, J. Thuriot, S. Paul, V. Ordomsky, A. Khodakov   +8 more
semanticscholar   +1 more source

First Principles Calculations for Hydrogenation of Acrolein on Pd and Pt: Chemoselectivity Depends on Steric Effects on the Surface.

Angewandte Chemie, 2016
The chemoselective hydrogenation of acrolein on Pt(111) and Pd(111) surfaces is investigated employing density functional theory calculations. The computed potential energy surfaces together with the analysis of reaction mechanisms demonstrate that ...
Sakari Tuokko, P. Pihko, K. Honkala
semanticscholar   +1 more source

Mechanistic Study of the Role of Substrate Steric Effects and Aniline Inhibition on the Bis(trineopentylphosphine)palladium(0)-Catalyzed Arylation of Aniline Derivatives

, 2017
The mechanism of the bis(trineopentylphosphine)palladium(0) (Pd(PNp3)2)-catalyzed coupling of aryl halides and aniline derivatives was studied in an effort to understand the role of substrate steric effects on the reaction.
Huaiyuan Hu, Fengrui Qu, Deidra L. Gerlach, K. H. Shaughnessy   +3 more
semanticscholar   +1 more source

From information theory to quantitative description of steric effects.

Physical Chemistry, Chemical Physics - PCCP, 2016
Immense efforts have been made in the literature to apply the information theory descriptors for investigating the electronic structure theory of various systems.
M. Alipour, Zahra Safari
semanticscholar   +1 more source

Sterically crowded aryloxide compounds of aluminum: electronic and steric effects

Organometallics, 1991
The mononuclear, four-coordinate aluminum compounds AlR 2 (BHT)L and AlR(BHT) 2 L [R=Me, Et; BHT=2,6-di-tert-butyl-4-methylphenoxide; L=2-Mepy, 4-Mepy, 2,6-Me 2 py, CH 3 CN, N(C 2 H 4 ) 3 CH, HNEt 2 , HN i Bu 2 , H 2 N t Bu,H 2 N n Bu, NH 3 , py•O] are obtained when AlR 3 is treated with the correct molar equivalent of BHT-H and the appropriate Lewis ...
Matthew D. Healy, Andrew R. Barron, Joseph W. Ziller   +2 more
openaire   +2 more sources

Evaluation of Substituent Effect in Z-Isomer Stability of Arylazo-1 H-3,5-dimethylpyrazoles: Interplay of Steric, Electronic Effects and Hydrogen Bonding.

Journal of Organic Chemistry, 2018
The electronic and steric effects of aryl substituents and the influence of hydrogen bonding in Z-isomer stability of phenylazopyrazole derivatives have been investigated.
S. Devi, M. Saraswat, S. Grewal, Sugumar Venkataramani   +3 more
semanticscholar   +1 more source