Synthesis and characterization by 19F and 207Pb NMR spectroscopy of the PbClnF6-n2- anions (n=0-6)

The inorganic chemistry of Pb(IV) has been extended by synthesizing the previously unknown series of octahedral mixed chlorofluoro-anions. PbClnF6-n^2-, where n = 1 - 5. The series has been generated in CH3CN solution by fluorination of (Et4N⁺)2PbCl6^2- with XcF2 and by halogen scrambling of mixtures of (Et4N⁺)2PbF6^2- and (Et4N⁺)2PhCl6^2-. The salt,'(Et4N⁺)2PbF6^2-, has been isolated and is the first example of a PbF6^2- salt that contains an organic cation. The entire series, consisting of ten anions and their isomers, has been characterized in CH3CN solution by ¹⁹F and ²⁰⁷Pb NMR spectroscopy and trends in the chemical shifts and lead-fluorine coupling constants discussed. © Gauthier-Villars.