Syntheses And Properties Of Amidine And Guanidine Compounds Containing Multi-amino Moieties

Amidine and guanidine compounds are very important organic compounds containing-N-C(=N)- moieties, of which guanidines are also known as the "amino formamidine". Amidine and guanidine derivatives have been applied in the pharmaceutical, pesticide, chemical and other fields. The syntheses and properties of these compounds are herein described in this thesis.(1) Two series of benzyl and alkyl benzamidine derivatives, including ten compounds, were synthesized and characterized by 1H NMR, 13 C NMR and IR spectroscopies. Their photophysical properties and thermal stability properties were also investigated; an excellent UV resistance effects of such compounds were found in the range of 280~370 nm(ε>5000) with εmax being more than 34,000. The influence of different metal ions on the photophysical properties of benzamidine compounds were understood, of which Zr4+ and Al3+ may bring hypochromic effects and blue shift phenomena in their UV spectra, while the fluorescence intensities accordingly increase and the blue shift of the maximum fluorescence emission wavelength also occurred. However, Pb2+ may also lead benzamidine derivatives to hypochromic effect and fluorescence enhancement in the UV spectra. The ten compounds have good thermal stability, over 300 oC quality to drop down, and the thermal stability of benzyl benzamidine derivatives is obviously better than that of alkyl benzamidine derivatives.(2) Synthetic methods and practical applications of guanidine compounds in medicine, veterinary drugs, antibacterial agent, surface active agent, catalyst, and ionic liquids are reviewed in detail. Twenty-one bi-[(aryl)amino] guanidine derivatives were prepared and characterized by 1H NMR, 13 C NMR and IR spectroscopies. And molecular structure of compound DG8 was comfirmed by single-crystal X-ray diffraction. To further explore the effects of such compounds on identification of halide anions, we have tested their color change on fluoride anion; and spectral changes with or without the fluoride anion in the solution were performed on the UV and fluorescence spectra. Because the hydrogen atom of guanidine group is positive, it is easy to produce the-H…F bond. Especially compounds DG8, DG11, DG16 and DG17 are quite obviously sensitive to color-change with the fluoride anion, which may infer that they can selectively recognize fluoride anion in the visibile light ranges.(3) Development of metal complexes with guanidine ligands are prespected in this section, the important reason is that the different guanidine compound s have a variety of resonant structures when coordinated with metal ions. Twenty-one tri-[(aryl)amino] guanidine derivatives were prepared and characterized by 1H NMR, 13 C NMR and IR spectroscopies. Furthermore, the sensing ability of fluoride anion by way of UV and fluorescence spectra along with the possible color-change was investigated. Because the center hydrogen atom of guanidine group in these compounds can form hydrogen bond with fluoride anion, so the results showed that tri-[(aryl)amino] guanidine derivatives can selectively recognize fluoride anion in the solution. Coordination reactions of several metal ions with tri-[(aryl)amino] guanidine derivatives were determined by the UV spectroscopy.