
%0 Journal Article
%A Becker, HD 
%A Skelton, BW 
%A White, AH 
%T Molecular Topology of Di(9-Anthryl)Ethanedione (9,9'-Anthril) and Some Generically Related Cyclic 1,2-Diketones
%J Australian Journal of Chemistry
%D 1991/02/01
%V 44
%N 2
%P 181-195
%K 
%R https://doi.org/10.1071/CH9910181
%U https://www.publish.csiro.au/paper/CH9910181 
%X The molecular structures of di (9-anthryl) ethanedione (9,9&#8242;-anthril) and those of four 1,2-diketones derived from 9,9&#8242;-anthril by way of intramolecular cycloadditions were investigated by single-crystal X-ray diffraction studies. Two crystal modifications of 9,9&#8242;-anthril were available and found to differ in the dihedral angles (43.9 and 178.3&#176;) about the 1,2-dicarbonyl moiety. The 1,2-dicarbonyl group of the cyclobutanedione moiety in the anthril 4&#960;+4&#960; cyclomer is associated with a dihedral angle of 2.6&#176;. In the anthril isomer derived by 4&#960;+2&#960; cycloaddition, an exceptionally long single bond is indicative of molecular strain. The molecular structures of a keto enol and of a novel 1,2-diketo substituted triptycene, both obtained from the 4&#960;+2&#960; cyclomer by acid-catalysed rearrangement and dehydrogenation, respectively, were established. The topological and spectroscopic differences between the keto en01 and its 1,2-diketo precursor are discussed. 
