Ferrocene- and ruthenocene-containing chalcones: A spectroscopic and electrochemical study

Abstract: Chalcones of the type Mc-CO–CH-CO–CH Mc-CO–CHh Mc=Fc=ferrocenyl or Rc=ruthenocenyl, and Ph=phenyl were synthesized. Synthesis was achieved by base catalyzed Claisen–Schmidt condensation of the appropriated acetyl and aldehyde in ethanol. Cyclic voltammetry in CH3CN in the presence of 0.1moldm−3 [N(Bu)4][PF6] revealed chemical and electrochemical reversible behaviour for the Fc/Fc+ couple and irreversible electrochemistry for the two electron Rc/Rc2+ couple. The potential ranges for the Fc/Fc+ couple varied in the range 138⩽ E°′⩽302mV while E pa for Rc/Rc2+ couple was between 358 and 510mV vs. FcH/FcH+, the internal standard. Chalcones with the carbonyl group adjacent to the metallocene, are more difficult to oxidize. [Copyright &y& Elsevier]