Coordination Non-Innocence and Redox Chemistry of Antimony Ligands
Abstract
The coordination chemistry of antimony-containing ligands has been historically understudied relative to phosphines and arsines due to the widely held perception that their properties varied little from their lighter congeners. Recent developments, however, have found that antimony ligands can display unique coordination and redox behavior which mimics that known for organoantimony species. Coordinated antimony centers can engage in secondary bonding interactions in which the incoming ligand can bind trans to the Sb-M bond or the Sb-R bond. This coordination non-innocent behavior bears potential utility in anion-sensing and tuning of the coordinated transition metal center. Transition metal stibine complexes also undergo two-electron redox chemistry, which can be localized at the metal or the antimony center. In the latter case, the resulting Sb(V) species can serve as a Z-type ligand to activate the coordinated transition metal center for electrophilic reactivity. With the future goal of further incorporating antimony-containing ligands into functional main group-transition metal heterobimetallic platforms for anion-sensing, catalysis, and other behaviors, the origin and consequences of their unique behavior must be further investigated.
In an effort to systematically investigate the coordination non-innocent behavior of antimony ligands, their complexes were compared to the analogous phosphorous and arsenic complexes. The effect of coordination non-innocent behavior on the Sb-M bond was also systematically studied. The redox behavior of transition metal stibines was further elucidated in a series of case studies. Finally, we provide proof of concept that coordination-non innocent behavior in antimony ligands can be utilized to activate adjacent transition metal centers for electrophilic catalysis.
Citation
Jones, James Stuart (2016). Coordination Non-Innocence and Redox Chemistry of Antimony Ligands. Doctoral dissertation, Texas A & M University. Available electronically from https : / /hdl .handle .net /1969 .1 /174269.