om200694r_si_001.pdf (294.66 kB)

Scorpionate Ligands Based on 2-Mercaptopyridine: A Ligand with a Greater Propensity To Sting?

Download (294.66 kB)
journal contribution
posted on 14.11.2011, 00:00 by Gavin Dyson, Alexander Zech, Benjamin W. Rawe, Mairi F. Haddow, Alexander Hamilton, Gareth R. Owen
The synthesis and characterization of the first platinum group metal complexes of the recently reported ligand [H2B­(mp)2] (where mp = 2-mercaptopyridyl) are presented herein. Addition of 2 equiv of Na­[H2B­(mp)2] to [MCl­(COD)]2 (where M = Rh, Ir; COD = 1,5-cyclooctadiene) leads to the hydride migration products [Rh­{κ3-SSB-BH­(mp)2}­(η3-C8H13)] and [Ir­(H)­{κ3-SSB-BH­(mp)2}­(η4-C8H12)], respectively. Structural characterization of the rhodium complex reveals a notably short rhodium–boron distance of 2.054(2) Å. The reactivity observed for the rhodium complex is different from that of all known scorpionate ligands, suggesting a higher propensity for hydride migration within the 2-mercaptopyridine-based ligands. The complex [Ir­(Cl)­{κ3-SSB-BH­(mp)2}­(η4-C8H12)], which is formed via hydride/halide exchange in chloroform, is also structurally characterized. The new complexes provide rare examples of metallaboratrane complexes where one hydrogen substituent remains at the boron center.