Synthetic access to low-coordinate Pb mono- and dications is in general impeded due to their poor solubility and highly electrophilic nature. However, the electrophilicity of these cations can be tamed by attaching them to electron-rich transition metals. Following this principle we have isolated low-valent Pb mono- ([(Cy _(3) P) _(2) Pt–PbCl] _(2) [AlCl _(4) ] _(2) , 8a ) and dications ([(Cy _(3) P) _(2) Pt(Pb)][AlCl _(4) ] _(2) , 11 ) in the coordination sphere of platinum. The same approach then has been implemented for the isolation of analogous low-valent Sn mono- ( 7a ) and dications ( 10 ). An energy decomposition analysis (EDA-NOCV) was performed to investigate the nature of Pt–Pb and Pb–Cl bonding in [(Cy _(3) P) _(2) Pt(PbCl _(2) )] ( 2 ), 8a and 11 . The results show that the Pt–Pb bonds in 8a and 11 are electron-sharing in nature, whereas that of the precursor 2 is a dative bond. The breakdown of attractive interactions in 2 , 8a and 11 reveals that the ionic interactions in the analyzed Pt–Pb and Pb–Cl bonds are always stronger than the covalent interactions, except for the Pb–Cl bond in 8a . The calculated D3 dispersion energies show that dispersion interactions play a key role in the thermodynamic stability of 2 , 8a and 11 .
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