Novel E,C,E'-pincer supported silyl cations (E, E' = O, S, Se, Au) were prepared in three steps starting from 2,6-F2C6H3SiMe2H (1a) and 2,6-Br2C6H3SiMe2H (1b), which were first converted in two complementary ways into 2,6-(Ph2P)(2)C6H3SiMe2H (2). The oxidation of 2 with H2O2 center dot urea, S-8, and Se-8 afforded 2,6-(Ph2PE)(2)C6H3SiMe2H (3a, E = O; 3b, E = S; 3c, E = Se) and 2-(Ph2PE)-6-(Ph2P)-C6H3SiMe2H (4b, E = S; 4c, E = Se), which were reacted to the E,C,E-supported silyl cations [2,6-(Ph2PE)(2)C6H3SiMe2](+) (5a, E = O, counterion Br-3(-); 5b, E = S, counterion B(C6F5)(4)(-); 5c, E = Se, counterion B(C6F5)(4)(-)), the E,C-supported silyl cations [2-(Ph2PE)-6-(Ph2P)C6H3SiMe2](+) (6b, E = S, not isolated; 6c, E = Se, not isolated), the O,C,S-supported silyl cation [2-(Ph2PS)-6-(Ph2PO)C6H3SiMe2](+) (7, counterion B(C6F5)(4)(-)) as well as the E,C,Au-supported silyl cations [2-(Ph2PAuC6F5)-6-(Ph2PE)C6H3SiMe2](+) (8b, E = S, counterion [B{3,5-(CF3)(2)C6H3}(4)](-); 8c, E = Se, [B{3,5-(CF3)(2)C6H3}(4)](-)) using Br-2, O-2, S-8, (tht)AuC6F5, Ph3C[B(C6F5)(4)] and Ph3C[B{3,5-(CF3)(2)C6H3}(4)]. All compounds were characterized by multinuclear (H-1, C-13, F-19, Si-29, P-31, Se-77) NMR spectroscopy, ESI MS spectrometry and X-ray crystallography (2, 3a center dot H2O, 3b, 3c, 4b, 5a, 5c, 7, 8b, 8c). The gas phase structures of 2, 3a-c, 5a-c (fully optimized) and 8b, 8c (single-point calculations) were studied at the B3PW91/6-311+G(2df,p) level of theory. A set of real-space bonding indicators (RSBIs) derived from the theoretically calculated electron and pair densities were analyzed utilizing the atoms-in molecules (AIM) and electron-localizability indicator (ELI-D) space partitioning schemes.
