Multi-electron reactivity of a cofacial di-tin(II) cryptand: partial reduction of sulfur and selenium and reversible generation of S3˙−

• Main Authors: Dai, Yizhe (Author), Wu, Gang (Author), Cummins, Christopher C. (Author), Stauber, Julia M. (Contributor), Miller, Peter G (Contributor), Nocera, Daniel G. (Author)
• Other Authors: Institute for Medical Engineering and Science (Contributor), Massachusetts Institute of Technology. Department of Biology (Contributor), Massachusetts Institute of Technology. Department of Chemical Engineering (Contributor), Massachusetts Institute of Technology. Department of Chemistry (Contributor), Nocera, Daniel G (Contributor)
• Format: Article
• Language: English
• Published: Royal Society of Chemistry, 2018-07-30T18:08:10Z.
• Subjects: Article
• Online Access: Get fulltext

Cofacial bimetallic tin( II ) ([Sn 2 ( m BDCA-5t)] 2-, 1) and lead( II ) ([Pb₂(mBDCA-5t)]²-, 2) complexes have been prepared by hexadeprotonation of hexacarboxamide cryptand m BDCA-5t-H₆ together with double Sn(II) or Pb(II) insertion. Reaction of 1 with elemental sulfur or selenium generates di-tin polychalcogenide complexes containing m -E and bridging m -E 5 ligands where E ¼ S or Se, and the Sn( II ) centers have both been oxidized to Sn( IV ). Solution and solid-state UV-Vis spectra of [( m -S 5 )Sn 2 ( m -S)( m BDCA-5t)] 2 ( 4 ) indicate that the complex acts reversibly as a source of S 3 c in DMF solution with a K eq ¼ 0.012 0.002. Reductive removal of all six chalcogen atoms is achieved through treatment of [( m -E 5 )Sn 2 ( m -E)( m BDCA- 5t)] 2 with PR 3 (R ¼ t Bu, Ph, O i Pr) to produce six equiv. of the corresponding EPR 3 compound with regeneration of di-tin( II ) cryptand complex 1.
National Science Foundation (U.S.) (CHE-1305124)