Abstract
Intramolecular (transannular) and intermolecular through-space interactions between chalcogen atoms have been described. This account includes the following three topics. (1) Various types of bis-chalcogenides and their mono-oxides, which have the two chalcogen atoms in close proximity in a molecule, give the dichalcogena dications upon the oxidation with two equivalents of NOBF 4 or treatment with one equivalent of triflic anhydride (Tf 2O). The stability of the dichalcogena dications increases in the order S<Se<Te. The dichalcogena dications with flexible scaffolds cause dealkylation via an S N1 type reaction to form chalcogenachalcogenonium salts and alkyl cations. (2) The reaction of 2,6-bis[(phenylthio- or phenylseleno)methyl]phenyl phenyl telluride or the corresponding Teoxide with NOBF 4 or Tf 2O affords the positively-charged hypervalent species, dicationic telluranes. Dicationic telluranes can be prepared by the remote oxidation through π-conjugation. The stable sulfenium cation can be isolated by taking advantage of 2,6-bis[(dimethylamino)methyl]phenyl ligand. (3) The remote oxygen migration and Pummerer reactions of p-bis(methylthio)-aromatic mono-oxides are discussed in light of an intermolecular through-space interaction between sulfur atoms, and a cyclic bis(dithia dication) dimer is proposed as an intermediate.
Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
