Synthesis, Electronic Structure, and Reactivities of Two-Sulfur-Stabilized Carbones Exhibiting Four-Electron Donor Ability

5 years ago

Synthesis, Electronic Structure, and Reactivities of Two-Sulfur-Stabilized Carbones Exhibiting Four-Electron Donor Ability

Ryo Iijima, Shigeru Nagase, Tomohito Morosaki, Wei-Wei Wang, Takayoshi Fujii, Tsubasa Suzuki

Bis(sulfane)carbon(0) (BSC; Ph2SCSPh2 (1)) is successfully synthesized by deprotonation of the corresponding protonated salt 1⋅HTfO. The diprotonated salt 1⋅(HTfO)2 as the starting material can be also easily accessed by the deimination of iminosulfane(sulfane)carbon(0) (iSSC)⋅HBF4. Density functional theory calculations revealed the peculiar electronic structure of 1, which has two lone pairs of electrons at the central carbon atom. The largest proton affinities (PA(1): 297.5 kcal mol−1; PA(2): 183.7 kcal mol−1) and the highest energy levels of the HOMOs (HOMO: −4.89 eV; HOMO−1: −5.02 eV) for 1 among the two-sulfur-stabilized carbones clearly indicate the strong donor ability of carbon center stabilized by two SII ligands. The donating ability of these lone pairs of electrons is demonstrated by the C-diaurated and C-proton-aurated complexes, which provide the first experimental evidence for two-sulfurstabilized carbones behaving as four-electron donors. Furthermore, the syntheses and application of AgI carbone complexes as carbone transfer agents are also reported. Two-sulfur-carbone family: The first bis(sulfane)carbone(0) (BSC) is accessed by the deprotonation of the corresponding protonated salt. The strongest donor ability of BSC among the two-sulfur-stabilized carbones results in the diprotonated salt BSC⋅H2. The four-electron donating ability of the two-sulfur-stabilized carbones is demonstrated by the structural analysis of aurated complexes.

Publisher URL: http://onlinelibrary.wiley.com/resolve/doi

DOI: 10.1002/chem.201700863