Synthesis, crystal structures, electrochemistry and nonlinear optical properties of a novel (D–A–D) biferrocenyl derivative: 2-Amino-4,6-diferrocenylpyrimidine

A novel donor–acceptor–donor (D–A–D) biferrocenyl derivative, 2-amino-4,6-diferrocenylpyrimidine, has been synthetized and characterized by 1H NMR, elemental analysis, IR and UV absorption spectroscopy, thermogravimetric analysis (TGA) and X-ray crystallography. The crystal structure revealed that the molecular configuration displayed a good coplanarity. The obtained cis-isomer showed a different arrangement due to the induced metal ion Cd(II). The electronic spectrum features were explained by density functional theory (DFT) which agreed well with the experimental data. The cyclic voltammetry (CV) showed the half wave potential of the compound was more positive than that of the standard ferrocene (Fc), indicating that the strong electron-withdrawing effect of the aminopyrimidine moiety made the ferrocene units more difficult to oxidize. Especially, the nonlinear optical (NLO) properties were determined by optical limiting and Z-scan techniques, which suggested a strong π-electron delocalization and a large polarizability in the molecule reasonably equipped for meeting the requirements for third-order NLO materials.

Graphical abstractA new (D–A–D) biferrocenyl derivative, 2-amino-4,6-diferrocenylpyrimidine, has been concisely synthesized and characterized. The cis-isomer showed different configurations due to the induced metal ion. The absorption spectra, cyclic voltammetry and nonlinear optical properties have been studied. The result suggested a strong electron delocalization and remarkable polarizability in the molecule.Figure optionsDownload full-size imageDownload as PowerPoint slideHighlights► A novel pyrimidine bridged biferrocenyl derivative has been concisely synthesized. ► The cis- and trans-configurational isomers were obtained at different conditions. ► The structure displayed a good coplanarity and strong electron delocalization. ► The electrochemical and remarkable NLO properties were emphatically studied.