Lariat ethers with fluoroaryl side-arms: a study of CF⋯metal cation interaction in the complexes of N-(o-fluoroaryl)azacrown ethers
作者:Petr K. Sazonov、Lidiya Kh. Minacheva、Andrei V. Churakov、Vladimir S. Sergienko、Galina A. Artamkina、Yuri F. Oprunenko、Irina P. Beletskaya
DOI:10.1039/b807199c
日期:——
CFmetal cation interaction. Cation binding constants (beta, evaluated by UV titration method), demonstrate that F-A15C5 and F(2)-A(2)18C6 form more stable complexes than their fluorine-free analogs. The effect depends on the nature of the metal cation and is at a maximum for hard, singly charged cations (up to 3 logbeta units for K(+) complex of F(2)-A(2)18C6). The X-ray structures of complexes [Pb(F
新套索状醚N-(邻氟苯基)氮杂15-冠-5(F-A15C5)和N,N'-双(邻氟苯基)二氮杂18-冠-6(F(2)-A(通过相应的氮杂冠醚的N-芳基化反应制备2)18C6)。在溶液中通过(1)H和(19)F NMR(在丙酮-d(6)中)和紫外光谱(MeOH)研究了配体与金属阳离子的相互作用,证实了F(2)-A的配合物的形成(2)具有C(+),Na(+),Ag(+),Ba(2 +),Pb(2+)的18C6和具有Na(+)的F-A15C5,并提供了CFmetal阳离子相互作用的证据。阳离子结合常数(β,通过紫外线滴定法评估),表明F-A15C5和F(2)-A(2)18C6比其不含氟的类似物形成更稳定的络合物。该效果取决于金属阳离子的性质,并且对于硬的单电荷阳离子最大(对于F(2)-A(2)18C6的K(+)络合物,高达3个logbeta单位)。配合物[Pb(F(2)-A(2)18C6)(H(2