Synthesis, Isolation, and Characterization of a Phenylsulfane-Selenolate Compound.

The first example of a stable phenylsulfaneselenolate species was synthesized in a one-step process and isolated as the tetraphenylphosphonium salt [PPh][PhSSe] as indicated by X-ray crystal structure analysis. Electrospray ionization mass spectrometry and NMR studies in solution showed the compound to enter a complex system of equilibria when dissolved. Computations suggested a high barrier for rotation around the C-S bond, indicating a π-system conjugated over the whole molecule.

Synthesis, Spectroscopic, and Structural Characterization of Organyl Disulfanides and a Tetrasulfanide.

Various room-temperature-stable monoorganylpolysulfanides of the form [X][RS] (X = [PPh], [PNP], [NEt]; R = Ph, -Bu, ≥ 2) were synthesized in a simple and versatile one-step process starting from sodium thiolates and elemental sulfur. The compounds were characterized by X-ray crystal structure analysis, NMR spectroscopy, microelemental analysis, and electrospray mass ionization spectrometry including collision-induced dissociation experiments. While these salts are well-defined species as crystals, they undergo complex equilibria in solution.

Alkyl Radical Generation by an Intramolecular Homolytic Substitution Reaction between Iron(II) and Trialkylsulfonium Groups.

Intramolecular, homolytic substitution reactions between iron(II) species and various trialkylsulfonium groups were directly observed in the gas phase upon collision-induced dissociation. In spite of the notoriously low reduction potential of trialkylsulfonium species and the mismatched oxidation potential of iron(II), the reactions proceed at moderate collision energies, forming an alkyl radical as well as a thioether coordinated to the iron. In contrast to classical homolytic substitutions, the attacking radical is a "metalloradical", namely iron(II) that is oxidized to iron(III) during the reaction.

S-Trifluoromethylation of Thiols by Hypervalent Iodine Reagents: A Joint Experimental and Computational Study.

The radical trifluoromethylation of thiophenol in condensed phase applying reagent 1 (3,3-dimethyl-1-(trifluoromethyl)-1λ(3),2-benziodoxol) has been examined by both theoretical and experimental methodologies. On the basis of ab initio molecular dynamics and metadynamics we show that radical reaction mechanisms favourably compete with polar ones involving the S-centred nucleophile thiophenol, their free energies of activation, ΔF(≠), lying between 9 and 15 kcal mol(-1). We further show that the origin of the proton activating the reagent is important.