Synthesis, electrochemical and thermodynamic studies of ferrocenazomethin hydroxyl benzenes with p- benzoquinone derivatives

Hanadi M. Arafa* and Shaeel A. Al-Thabaiti

*Department of Chemistry, Faculty of Girls Education, P.O.Box 741, Jeddah, Tabouk - 71491 (Saudi Arabia). Department of Chemistry, Faculty of Science, King Abdul Aziz University, P.O.Box 80203 Jeddah 21589 (Saudi Arabia).

Received on August 08, 2009 and accepted on October 15, 2009

ABSTRACT

New Ferrocene Schiff base compounds based on the strong ferrocene moity and hydroxy benzaldehyde derivatives exhibited increased electron donor ability were synthesized via described methods. The acceptors used in this investigation are 2,3-dichloro-5,6-dicyano-1,4- benzoquinone (DDQ), p-chloranil (CHL) and chloranilic acid (CHLC). The reactions of donor and acceptor indicate the formation of 1:1 charge-transfer complexes based on the electronic absorption and the spectroscopic studies reveal that charge-transfer unstable in solution and required some time for stabilization. Electrochemical properties of these new compounds were studied using conductometric technique and ultra violet- visible spectra. The absorption spectra showed a red-shift with a slight increase in the absorption intensities. Kinetic studies of the reaction in ethanol at different temperatures reveal that the rate of reaction is k dependence. The energy of activation Ea was determined further more the thermodynamic parameters, enthalpy of reactions H and entropy DS were calculated.

Keywords : Ferrocene, Charge transfer, Conductance, Kinetic and Thermodynamic studies.