Four novel circlet ferrocenophanes: 1,9-dicarbonyl-2,8-dioxo-5-(4-fluoro)phenyl-N-[9] ester ferrocenophane a, 1,9-dicarbonyl-2,8-dioxo-5-(4-methyl)phenyl-N-[9] ester ferrocenophane b, 1,9-dicarbonyl- 2,8-dioxo-5-(4-methoxy)phenyl-N-[9] ester ferrocenophane c, 1,9-dicarbonyl-2,8-dioxo-5-(4-nitro)phenyl- N-[9] ester ferrocenophane d were synthesized starting from ferrocene via 1,1'-diacetylferrocene, 1,1'- ferrocene-dicarboxylic acid, 1,1'-ferrocene-di(carbonyl chloride) with dihydroxyethyl aniline under high dilute condition. The ester ferrocenophanes were characterized by UV, ¹H NMR, IR, elemental analysis and matrix assisted laser desorption/ionization-time of flight (MALDI-TOF) MS. The crystals of ester ferrocenophane a were obtained and the crystal structure was determined by X-ray diffraction.

Key words: ester ferrocenophanes, synthesis, characterization, crystal structure