An investigation of the formation of 1,3,5-heterosubstituted benzene rings by cyclo-condensation of acetyl-substituted organometallic complexes

The cyclocondensation of acetylferrocene and acetylcymantrene catalyzed by SiCl4 in ethanol yields a mixture of 1,3,5-trisubstituted benzenes and the intermediate 3,1-disubstituted (E)-2-buten-1-ones, including all the homo- and heterometallic species, which were separated and quantified by HPLC. The relative yields of these species are determined by the different ability of the organometallic groups to stabilize the cationic intermediates that participate in the reaction mechanism, which is measurable as the basicity of the starting materials. The X-ray crystal structures of 1-cymantrenyl-3,5-diferrocenylbenzene and (E)-3-cymantrenyl-1-ferrocenyl-2-buten-1-one are described within this report.