Darstellung und Eigenschaften, Reaktionen und Anwendungsmöglichkeiten von Radialenen

Abstract

Professor Giinther Maier zum 60. Geburtstag gewidmetRadialene sind Alicyclen, bei denen jedes Ringatom sp2-hybridisiert ist und eine exocyclische C-C-Doppelbindung tragt. Sie haben wegen ihrer ungewohnlichen Molekiil-und Elektronenstrukturen die Aufmerksamkeit der Synthesechemiker ebenso geweckt wie die der Theoretiker. Gezielte und effiziente Synthesen bleiben trotz erheblicher Fortschritte in jiingster Zeit nach wie vor eine Herausforderung, und das Studium ihrer chemischen Reaktivitat bietet noch viele Freiraume. In jiingster Zeit sind auch Materialwissenschaftler auf der Suche nach organischen Leitern und Ferromagneten auf diese Verbindungen aufmerksam geworden.

Planar [6]Radialenes: Structure, Synthesis, and Aromaticity of Benzotriselenophene and Benzotrithiophene

“…[10] In contrast to [3]-, [4]-, and [5]radialenes, [6]radialenes (of type 1) have a chair conformation, according to both experimental and theoretical studies. [1,2,11] Perylene and triphenylene may not be considered as radialenes, because the p electrons are delocalized over an aromatic sextet. [2] On the other hand, the condensedthiophene-fused compounds 2 [12] and 3, [13] which are isoelectronic with perylene, belong to the [6]radialene family.…”

“…[6]radialene, 1) are a relatively modern class of alicyclic hydrocarbons in which all carbon atoms in the ring are sp 2 hybridized and there are as many exocyclic double bonds as possible. [1,2] The first radialene, 7,8,9,10,11,12-hexamethyl [6]radialene, was prepared by Hopff and Wick in 1961. [3] Radialenes and their derivatives have been the subject of significant theoretical and experimental interest.…”

“…[1, 2, 4a] The parent [3]-, [4]-, [5]-, and [6]radialenes polymerize at room temperature and are unstable in air; however, many stable derivatives are known. [1,2] It has been found experimentally that [3]- [7] and [4]radialenes [8] usually have a planar structure. [9] [5]Radialenes, such as decamethyl [5]radialene, usually have a twistedenvelope or half-chair conformation.…”

“…[3] Radialenes and their derivatives have been the subject of significant theoretical and experimental interest. [1,2,4,5] New approaches to the synthesis of radialenes have been developed, and these structures have become important building blocks for organic conductors and ferromagnets. [1,2,6] Radialenes are also of considerable interest because of their exocyclic double bonds, aromaticity, and conjugation.…”

“…[1,2,4,5] New approaches to the synthesis of radialenes have been developed, and these structures have become important building blocks for organic conductors and ferromagnets. [1,2,6] Radialenes are also of considerable interest because of their exocyclic double bonds, aromaticity, and conjugation. [1, 2, 4a] The parent [3]-, [4]-, [5]-, and [6]radialenes polymerize at room temperature and are unstable in air; however, many stable derivatives are known.…”