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.