Dynamic Behavior of 1,5-Anthrelene unit incorporated in Structures of Anthracene-Acetylene Cyclic Oligomers

Abstract

We have studied dynamic behavior of 1,8- and 9,10-anthrylene-acetylene cyclic oligomers incorporated with various aromatic rings. We found that oligomers with a phenylene or a 1,5-naphthylene unit underwent rapid rotation of the aromatic ring. We report the synthesis and structure of this type of oligomer with a 1,5-anthrylene unit. This aromatic unit was introduced into the cramp-like acyclic trimer by desilylation and Sonogahira reaction to restrict the rotation of the unit. The 1H NMR spectra gave signals expected for a C2 symmetric structure, and this signal pattern was retained at 140 C.