Chemistry of anthracene–acetylene oligomers. XVII. Synthesis, structure, and dynamic behavior of 1,8-anthrylene pentamers and hexamers with acetylene linkers
rigid structure with strainedalkyne carbons. Meanwhile, out of several possible conformers the hexamers preferred to take parallelogram-prism structures due to transannular π⋯π interactions, and conformational interconversions via rotation about the acetylene axes took place rapidly at room temperature. NMR spectra and electronic spectra are discussed on the basis of molecular structures. The enantiomers
Strained and Fluxional Macrocyclic Framework of Anthracene–Diacetylene Cyclic Pentamers
作者:Manami Yoshikawa、Sakiko Imigi、Kan Wakamatsu、Tetsuo Iwanaga、Shinji Toyota
DOI:10.1246/cl.130100
日期:2013.5.5
Macrocyclic oligomers with five 1,8-anthrylene units and five diacetylene linkers were synthesized by successive coupling reactions. DFT calculations and variable temperature NMR measurements revealed that the cyclic framework is stained and fluxional, and each anthracene unit moves rapidly around all possible orientations.