1612838-81-9Relevant articles and documents
Design and synthesis of the first triply twisted Moebius annulene
Schaller, Gaston R.,Topic, Filip,Rissanen, Kari,Okamoto, Yoshio,Shen, Jun,Herges, Rainer
, p. 608 - 613 (2014)
As long as 50 years ago theoretical calculations predicted that Moebius annulenes with only one π surface and one edge would exhibit peculiar electronic properties and violate the Hueckel rules. Numerous synthetic attempts notwithstanding, the first singly twisted Moebius annulene was not prepared until 2003. Here we present a general, rational strategy to synthesize triply or even more highly twisted cyclic π systems. We apply this strategy to the preparation of a triply twisted [24]dehydroannulene, the structure of which was confirmed by X-ray analysis. Our strategy is based on the topological transformation of 'twist' into 'writhe'. The advantage is twofold: the product exhibits a lower degree of strain and precursors can be designed that inherently include the writhe, which, after cyclization, ends up in the Moebius product. With our strategy, triply twisted systems are easier to prepare than their singly twisted counterparts.
