このページは機械翻訳されています。他のページは英語で表示される場合があります。 View in English

光触媒CO2メタネーションを促進するシナージスピンポラライゼーション効果を持つ空間的に隣接するリドックスサイト

  • 0Key Laboratory for Advanced Materials, Joint International Research Laboratory of Precision Chemistry and Molecular Engineering, Feringa Nobel Prize Scientist Joint Research Center, School of Chemistry and Molecular Engineering, Shanghai Engineering Research Center for Multimedia Environmental Catalysis and Resource Utilization, East China University of Science & Technology, Shanghai 200237, China.

まとめ

この要約は機械生成です。

関連する概念動画

Photochemical Electrocyclic Reactions: Stereochemistry 01:26

1.8K

The absorption of UV–visible light by conjugated systems causes the promotion of an electron from the ground state to the excited state. Consequently, photochemical electrocyclic reactions proceed via the excited-state HOMO rather than the ground-state HOMO. Since the ground- and excited-state HOMOs have different symmetries, the stereochemical outcome of electrocyclic reactions depends on the mode of activation; i.e., thermal or photochemical.
Selection Rules: Photochemical Activation

Thermal and Photochemical Electrocyclic Reactions: Overview 01:26

2.3K

Electrocyclic reactions are reversible reactions. They involve an intramolecular cyclization or ring-opening of a conjugated polyene. Shown below are two examples of electrocyclic reactions. In the first reaction, the formation of the cyclic product is favored. In contrast, in the second reaction, ring-opening is favored due to the high ring strain associated with cyclobutene formation.

Electrocyclic reactions are highly stereospecific. For a substituted polyene, the stereochemical outcome...

Reduction of Alkenes: Asymmetric Catalytic Hydrogenation 02:17

3.3K

Catalytic hydrogenation of alkenes is a transition-metal catalyzed reduction of the double bond using molecular hydrogen to give alkanes. The mode of hydrogen addition follows syn stereochemistry.
The metal catalyst used can be either heterogeneous or homogeneous. When hydrogenation of an alkene generates a chiral center, a pair of enantiomeric products is expected to form. However, an enantiomeric excess of one of the products can be facilitated using an enantioselective reaction or an...

Cycloaddition Reactions: MO Requirements for Photochemical Activation 01:12

2.1K

Some cycloaddition reactions are activated by heat, while others are initiated by light. For example, a [2 + 2] cycloaddition between two ethylene molecules occurs only in the presence of light. It is photochemically allowed but thermally forbidden.

Thermally-induced [2 + 2] cycloadditions are symmetry forbidden. This is because the ground state HOMO of one ethylene molecule and the LUMO of the other ethylene are out of phase, preventing a concerted suprafacial-suprafacial overlap.
Absorption...