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 ¹H NMR, the stability of the complex of L with Pb(ClO₄)₂ in [²H₆]acetone was estimated (log β = 0.9).