Results 321 to 330 of about 280,815 (357)

Engineering an alcohol dehydrogenase with enhanced activity and stereoselectivity toward diaryl ketones: reduction of steric hindrance and change of the stereocontrol element

Catalysis science & technology, 2020
Engineering an alcohol dehydrogenase with enhanced activity and stereoselectivity toward diaryl ketones: reduction of steric hindrance and change of the stereocontrol element.
Kai Wu, Zhijun Yang, Xiangguo Meng, Rong Chen, Jian-Feng Huang, L. Shao   +5 more
semanticscholar   +1 more source

Steric hindrance of diffusion controlled reactions

Journal of Molecular Liquids, 1984
Abstract For diffusion controlled reactions in solution a theory is proposed which includes the diffusion process, the lifetime of an encounter complex, and the rotation of the reacting species in the encounter complex. For some types of reaction the analytical equations of this scheme are solved and discussed.
M.A. Lopez-Quintela, J. Samios, W. Knoche   +2 more
openaire   +1 more source

On-Surface Growth of Single-Layered Homochiral 2D Covalent Organic Frameworks by Steric Hindrance Strategy.

Journal of the American Chemical Society, 2020
Investigation of chirality in on-surface synthesis is of significance not only for fabricating atomically precise covalently bonded chiral species but also for unveiling chiral phenomena involving chemical reactions.
Cheng Lu, Yi-Ping Mo, Y. Hong, Ting Chen, Zhi-Yong Yang, L. Wan, Dong Wang   +6 more
semanticscholar   +1 more source

Origin of steric hindrance in ethane

International Journal of Quantum Chemistry, 1994
AbstractSteric hindrance has been regarded as a result of nonbonding atomic repulsion and measured in terms of empirically obtained van der Waals radii. The authors sought the cause of steric hindrance using the partial derivatives of the energy‐components with respect to a nuclear coordinate.
Hiroaki Tokiwa, Hiroshi Ichikawa
openaire   +1 more source

Unraveling Dual Aggregation-Induced Emission Behavior in Steric-Hindrance Photochromic System for Super Resolution Imaging.

Angewandte Chemie, 2019
Aggregation-induced emission (AIE) has attracted increasingly attention in a variety of applications due to the strong fluorescence emission in solid state. However, it still remains challenging for photoresponsive AIE materials with light modulation due
Hong Yang, Mengqi Li, Chong Li, Qianfu Luo, Mingqiang Zhu, H. Tian, Weihong Zhu   +6 more
semanticscholar   +1 more source

Domain growth kinetics and steric hindrance

Phase Transitions, 1991
Abstract We propose a simple model on which the effects of steric hindrance on domain growth after deep quenches can be studied. The work is motivated by recent experiments on cyanoadamantane. We observe extremely slow domain growth which is unusual for systems with non-conserved order parameter and non-diffusive (Glauber) dynamics.
Willart, J.-F., Naudts, Jan, Descamps, M.   +2 more
openaire   +2 more sources

High‐Efficiency As‐Cast Organic Solar Cells Based on Acceptors with Steric Hindrance Induced Planar Terminal Group

Advanced Energy Materials, 2019
A series of alkyl, alkoxyl, and alkylthio substituted A–π–D–π–A type nonfullerene acceptors (NFAs) IDTCN‐C, IDTCN‐O, and IDTCN‐S are designed and synthesized.
Yahui Liu, Miao Li, Jinjin Yang, Wenyue Xue, Shiyu Feng, Jinsheng Song, Zheng Tang, Wei Ma, Zhishan Bo   +8 more
semanticscholar   +1 more source

Steric hindrance in butadiene and ethylene

Tetrahedron, 1970
Abstract The structure of ethylene, trans - and cis -butadiene was determined theoretically, based on self consistent steric analysis. The calculated structures agree with the known experimental data. The energy path of the cis-trans isomerization of butadiene was calculated both for the ground state and the first excited state.
openaire   +1 more source

STERIC HINDRANCE AND HEATS OF FORMATION

Nature, 1943
IN the low-temperature polymerization of isobutene by boron fluoride, BF3, the heat of polymerization, which has been found to be in the neighbourhood of 10 kcal. per mole, is lower than would be expected on the basis of theoretical calculations1. Both chemical1 and X-ray2 evidence support the head-to-tail chain-structure:
A. G. EVANS, M. POLANYI
openaire   +1 more source

Regioselective Cross-Metathesis Reaction Induced by Steric Hindrance

Organic Letters, 2004
[reaction: see text] When hexa-1,5-dien-3-ol is protected with bulky groups, a regioselective cross-metathesis reaction can take place at the C5-C6 double bond.
Samir, BouzBouz, Rebecca, Simmons, Janine, Cossy   +2 more
openaire   +2 more sources