New chiral calix[4]arene-based diol-diamides 1a, 1b, tetraamides 2a, 2b and 7 as well as achiral diamide 3 and tetraamides 4-6 were prepared. The conformation of 1 has been studied in solution by NMR and in solid state by X-ray crystallography. The pinched-cone conformation of the calix[4]arene skeleton in 1 was found to be stabilized by a circular array of hydrogen bonds formed by two phenolic O-H and two amidic N-H bonds at lower rim. Whereas no significant complexation of Na+ was observed in solution for diamides 1 and 3, tetraamides 2, 4, 5, and 6 give strong complexes with Na+ as confirmed by NMR titrations of 2 and 4. The influence of anions and the solvents used on complexation ability of 2 towards Na+ is negligible.
新的手性卡立克斯[4]芳烃基双醇-二酰胺化合物1a、1b、四酰胺化合物2a、2b和7,以及无手性二酰胺化合物3和四酰胺化合物4-6已经制备。通过NMR和X射线晶体学在溶液和固态下研究了1的构象。发现1中卡立克斯[4]芳烃基骨架的捏合锥构象由下缘的两个酚羟基和两个酰胺基氮-氢键形成的环形氢键稳定。虽然在溶液中没有观察到1和3的二酰胺化合物与Na+的显着络合,但通过NMR滴定实验证实2、4、5和6的四酰胺化合物与Na+形成强络合物。溶剂和阴离子对2的络合能力对Na+的影响可以忽略不计。