Synthesis, Stabilities, and Redox Behavior of Mono-, Di-, and Tetracations Composed of Di(1-azulenyl)methylium Units Connected to a Benzene Ring by Phenyl- and 2-Thienylacetylene Spacers. A Concept of

详细信息    查看全文

• 作者：Shunji Ito ; Koji Akimoto ; Jun Kawakami ; Akio Tajiri ; Taku Shoji ; Hiroyuki Satake ; Noboru Morita
• 刊名：Journal of Organic Chemistry
• 出版年：2007
• 出版时间：January 5, 2007
• 年：2007
• 卷：72
• 期：1
• 页码：162 - 172
• 全文大小：434K
• 年卷期：v.72,no.1(January 5, 2007)
• ISSN：1520-6904

文摘

This paper describes the preparation of two tetracations 4a⁴⁺ and 4b⁴⁺ composed of di(1-azulenyl)methylium units based on a new structural principle of a cyanine-cyanine hybrid for the design ofelectrochromic materials with two color changes. Di- and monocations 5a²⁺, 5b²⁺ and 6a⁺, 6b⁺ composedof di(1-azulenyl)methylium units were also prepared for the purpose of comparison. The pK_R⁺ values ofthe tetracations are rather high despite their tetracationic structure, although the stability of these cationsdecreases with the increase of the number of the existing cation units. The cyclic voltammetry (CV) ofthese cations revealed the presumed multielectron redox properties. However, the tetracations did notexhibit the idealized electrochemical behavior, in which subsequent two-electron reduction was presumedas the cyanine-cyanine hybrid, probably due to the less effective electrochemical interaction among thepositive charges. The scope of the creation of the novel polyelectrochromic materials taking the newstructural principle is demonstrated by these examples.