Crystal structure of diaqua[N,N′-bis(tetrafluoropyridyl)diaza-18-crown-6]lead(II) perchlorate:: The effect of perfluoroaromatic groups on the stucture of the complex

According to X-ray analysis data, in the [PbL(H2O)(2)](2+) complex cation [L = N,N'-di(tetrafluoropyridyl)diaza-18-crown-6], the Pb atom is coordinated asymmetrically by four O(1)-O(4) atoms of the macrocycle and two O(5), O(6) atoms of water molecules, and, additionally, at longer distances, by the ortho-fluorine atoms F(4), F(5) of two perfluoropyridyl rings and the N(1), N(2) atoms of the macrocycle, thus demonstrating a partial localization of the lone electron pair of Pb. Using H-1 NMR, the stability of the complex of L with Pb(ClO4)(2) in [H-2(6)]acetone was estimated (log beta = 0.9).