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Updated: Jul 6, 2026

Preparation of Monodomain Liquid Crystal Elastomers and Liquid Crystal Elastomer Nanocomposites
12:21

Preparation of Monodomain Liquid Crystal Elastomers and Liquid Crystal Elastomer Nanocomposites

Published on: February 6, 2016

合成,特徴付け,およびシリカを支えるカチオンのサイクロペンタディエニルジルコニウム複合体のエチレンポリメリゼーションにおける活性

Nicolas Millot1, Sophie Soignier, Catherine C Santini

  • 1Laboratoire de Chimie Organométallique de Surface, UMR 9986 CNRS--ESCPE Lyon, 43 bd du 11 Novembre 1918, F-69626 Villeurbanne Cedex, France.

Journal of the American Chemical Society
|July 20, 2006
PubMed
まとめ

シリカで支えられているジルコニウム複合体は,異なる表面環境を示し,その反応性に影響を与えます. 共同結合ジルコニウム触媒は",浮遊"カチオン触媒と比較して,エチレンポリメリゼーションにおいてより高い活性を示しています.

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Thermal and Photochemical Electrocyclic Reactions: Overview

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.
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Photochemical Electrocyclic Reactions: Stereochemistry

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Cycloaddition Reactions: Overview

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[4+2] Cycloaddition of Conjugated Dienes: Diels–Alder Reaction

The Diels–Alder reaction is an example of a thermal pericyclic reaction between a conjugated diene and an alkene or alkyne, commonly referred to as a dienophile. The reaction involves a concerted movement of six π electrons, four from the diene and two from the dienophile, forming an unsaturated six-membered ring. As a result, these reactions are classified as [4+2] cycloadditions.
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