Electrochemical and Spectroscopical Characterization of Ferrocenyl Chalcones

Abstract

We report on the electrochemical and spectroscopical characterization of 10 ferrocenyl chalcones. These compounds were synthesized via the Claisen–Schmith condensation from acetylferrocene and the corresponding benzaldehyde or pyridine carboxaldehyde. The compounds were obtained in good yields (60%) and purified by recrystallization. All compounds exhibit a quasi-reversible electrochemical behavior and chemical reversibility, as evidenced by ΔEnormalp of 72–90 mV and Ipa/Ipc values equal to 1.0–1.17. The redox formal potential (Eo′) for these compounds range between 665 and 774 mV. The heterogeneous electron-transfer rate constants calculated from the Nicholson method are in the range of (2.0–4.4)×10−2cm/s . Their diffusion coefficients are on the order of (1.65–3.7)×10−5cm2/s , and the number of electrons transferred equals 1. 1-ferrocenyl-3-( p-N,N -dimethylaminophenyl)prop-2-en-1-one shows a behavior similar to dimethylaniline and undergoes electropolymerization, producing cationic oligomers and dimeric species. The UV/visible spectra show the characteristic bands for aromatic systems in the UV region (200 and 280 nm) and bands in the visible (400 and 500 nm). The molar absorbance coefficient (ε) values are in the ranges (2.1–7.5)×104L/(molcm) for λmax of 200–300 nm and (1.8–17.6)×102L/(molcm) for λmax of 300–500 nm.

Synthesis, characterization and DNA binding studies of organoantimony(V) ferrocenyl benzoates

“…The absorption coefficients varied from 3.84 Â 10 4 to 6.60 Â 10 2 M À1 cm À1 . The values are in close agreement with those reported for ferrocenyl chalcones [43]. The greater extinction coefficient of 5 (1.87 Â 10 3 M À1 cm À1 ) at 460 nm as compared to 4 (6.90 Â 10 2 M À1 cm À1 ) at 451 nm is attributed to the more effective electron withdrawing ability of eCOOH at para position thus making the cyclopentadienyl ring to act as a weak donor.…”

Synthesis and characterization of novel ferrocenyl chalcone ammonium and pyridinium salt derivatives

“…(Table 1) The salts were successfully synthesized in 1 h under reflux conditions without the need for purification. Chalcone salt 1h was previously reported by us [15] using 2-methyl THF, for 3 h at reflux under nitrogen atmosphere, albeit in a lower yield. Changing the solvent from 2-methyl THF to toluene produced a 73% yield of the salt.…”

“…If the value of the slope is higher than 0.5, there is a possibility that the redox process is controlled by the adsorption of the compound to the electrode surface. [15]…”

“…Using a Claisen-Schmidt condensation reaction, the synthesis of eight amine and pyridine substituted chalcones was achieved (Figure 2). The synthesis of the precursors chalcones (1a–1d) has been previously reported by us [15], whereas all the others are known. [11, 16–18].…”

Synthesis, Characterization, and Computational Study of New Ferrocene‐Based Schiff Bases as Potential Nonionic Surfactants

“…ΔEp values are much higher than the expected Nernstian value of 59 mV per electron and unequal cathodic and anodic current ensures the electrochemically quasi‐reversible redox processes of all the synthesized ferrocenes (Cardona et al, ). Only ferrocene has been reported to register well‐defined reversible redox signals (Pournaghi‐Azar and Ojani, ).…”