Circulene

Circulene

Aromatic Helicenes

Published in Klaus D. Sattler, st Century Nanoscience – A Handbook, 2020

Conceptually, helicenes are counterparts of circulenes (members of a larger cycloarene family) that can formally be designed by fusing the terminal rings of a helicene molecule (ideally in an ortho fashion) (C. Buttrick and T. King, 2017; Stepień et al., 2017; Rickhaus et al., 2016, 2017). Thus, circulenes are macrocyclic arenes in which a central polygon is completely surrounded and fused by mostly aromatic rings. There are two unique examples of helicene-derived circulene-like molecules that are formed by either intramolecular addition of an aryne intermediate to its own backbone providing a [6]circulene derivative 98/99 as observed by Katz et al. (Wang et al., 2004) or, after irradiation with a fluorescent lamp to undergo a reversible [6 + 6] photocycloaddition, [7]saddlequat 100 (an isolable conformer of the more stable corresponding helquat 102), which forms a photo-stationary mixture with the chiral [8]circulenoid 101 as described by Teplý, Slavíček et al. (Severa et al., 2012) (Figure 4.24).

A study of the aromaticity of thia[7]circulene isomers

View Article

Journal Information

Published in Molecular Physics, 2022

Yang Yang, Satewaerdi Helili, Ablikim Kerim

Circulene is a macrocyclic aromatic molecule in which benzene rings are fused to form a closed circle [1,2]. Among them, [7]circulene (pleiadannulene) is the segment compound of non-classical fullerene isomers. [7]Circulene was first synthesised by Yamamoto et al. [3] in 1983. In 1996, a different synthetic method of [7]circulene was reported [4]. Sulphur atom substitution on [7]circulenes was reported by Dopper et al. [5,6].

Explore chapters and articles related to this topic

Aromatic Helicenes

A study of the aromaticity of thia[7]circulene isomers