A new calix[4]arene, functionalized with two thioamide moieties and with two allylic groups at the lower rim and the upper rim, respectively, and fixed in the 1,3-alternate conformation has been synthesized and its complexing properties towards Pb2+, Hg2+, Cd2+ and Na+ have been determined by UV–Vis titrations and by 1H NMR spectroscopy in organic media.The stoichiometries of lead and mercury complexes (1 ∶ 1) were at first determined by the mole ratio method and by Job plots. The speciation of the two systems was obtained making use of two different multiwavelength and multivariate treatments of spectral data. The computer treatment of the data confirmed the 1 ∶ 1 stoichiometry for the two complexes and gave reliable values for the corresponding stability constants (log KPb
 = 7.7; log KHg
 = 7.8). The ligand shows a high selectivity
 for lead and mercury over cadmium and sodium ions which are not complexed at all.Structural and conformational properties of the two complex species were obtained by 1H NMR spectroscopy. 1H NMR data show that, although having the same stoichiometry, the lead and mercury interact with the ligand molecule in a different manner.
                                    一种新的杯[4]
芳烃,其功能化部分由两个
硫代酰胺基团组成,下缘和上缘分别有两个烯丙基,以1,3交替构象固定,其与Pb2+、Hg2+、Cd2+和Na+的络合性质已通过UV-Vis滴定和有机介质中的1H NMR光谱测定。
铅和
汞络合物(1∶1)的
化学计量最初是通过摩尔比法和Job图确定的。利用两种不同的多波长和多变量处理光谱数据,获得了两个系统的形态。对数据的计算机处理证实了两个络合物的1∶1
化学计量,并给出了相应的稳定常数的可靠值(log KPb=7.7;log KHg=7.8)。
配体对
铅和
汞表现出很高的选择性,而对
镉和
钠离子则完全没有络合。通过1H NMR光谱获得了两种络合物形态的结构和构象性质。1H NMR数据显示,尽管具有相同的
化学计量,但
铅和
汞与
配体分子的相互作用方式不同。