Collect. Czech. Chem. Commun. 2010, 75, 1023-1040
Published online 2010-10-04 08:43:08

Synthesis, crystal structures and electrochemistry of ferrocenyl-substituted 1,3,4-oxadiazoles

Jiří Tauchman, Jakub Trnka, Ivana Císařová and Petr Štěpnička*

Charles University in Prague, Faculty of Science, Department of Inorganic Chemistry, Hlavova 2030, 128 40 Prague 2, Czech Republic


Two ferrocenyl-substituted 1,3,4-oxadiazoles, 2-ferrocenyl-1,3,4-oxadiazole (1) and 2,5-diferrocenyl-1,3,4-oxadiazole (2), have been prepared from the corresponding hydrazides, (ferrocenecarbonyl)hydrazine (3) and 1,2-bis(ferrocenecarbonyl)hydrazine (4), and characterized by conventional spectroscopic methods (IR, NMR, MS) and elemental analyses. The solid-state structures of 1, 2 and 4 have been determined by single-crystal X-ray diffraction analysis. The redox behavior of 1 and 2 was studied by electrochemical methods. Compound 1 underwent a reversible one-electron oxidation attributed to the ferrocene/ ferrocenium couple (Eo′ = +0.28 V vs ferrocene/ferrocenium). On the other hand, compound 2 showed two closely separated anodic waves corresponding to two consecutive redox changes, indicating some degree of electronic communication between the ferrocenyl moieties in positions 2 and 5 at the 1,3,4-oxadiazole ring.

Keywords: Ferrocene; Heterocycles; 1,3,4-Oxadiazoles; Electrochemistry; Crystal structure.

References: 29 live references.