41140-00-5Relevant academic research and scientific papers
Dications of fluorenylidenes. The effect of substituent electronegativity and position on the antiaromaticity of substituted tetrabenzo[5.5]fulvalene dications
Levy, Amalia,Rakowitz, Amber,Mills, Nancy S.
, p. 3990 - 3998 (2007/10/03)
Oxidation of 3,6-disubstituted tetrabenzo[5.5]fulvalenes by SbF5 results in the formation of dications that behave like two antiaromatic fluorenyl cations connected by a single bond. Both fluorenyl systems exhibit the paratropic shifts and nucleus independent chemical shifts (NICS) characteristic of antiaromatic species. Comparison with analogous 2,7-disubstituted tetrabenzo[5.5]fulvalenes reveals that the antiaromaticity of the substituted ring system can be altered substantially by changes in the placement of the substituents, possibly due to changes in the delocalization of charge in the system. Substituents in the 3,6-position decrease the antiaromaticity because of the increase in the benzylic resonance compared to 2,7-substituents.
Friedel-Crafts reaction of toluene with oxalyl chloride
Sakaino,Sugawara,Terao,Fujiwara,Mori,Maeda
, p. 271 - 275 (2007/10/03)
By the Friedel-Crafts reaction of toluene with oxalyl chloride, three kinds of fluorene derivatives (c, d, e), naphthalene derivative f, fluorenone derivative g, were obtained in addition to 4,4′-dimethyl benzophenone b.. In the compounds (c, d, e, f, g), c shows thermochromism above 135°C in solution, while e emits phosphorescence and f exhibits fluorescence at room temperature in the solid states.
