Ruthenium-benzocrownether complexes: Synthesis, structures, catalysis and immobilisation in ionic liquids
A facile pathway to [RuCl<sub>2</sub>(η<sup>6</sup>-benzocrownether)]<sub>2</sub> complexes is described and crystal structures of the complexes [RuCl<sub>2</sub>(η<sup>6</sup>-benzo-15-crown-5)]<sub>2</sub> and [RuCl<sub>2</sub>(η<sup>6</sup>-dibenzo-18-crown-6)]<sub>2</sub> are reported. The complexes were derivatised with (1S,2R)-2-amino-1,2-diphenylethanol and evaluated in the enantioselective transfer-hydrogenation of acetophenone. The effect of complexation of different alkaline metals (Na, K, Cs) within the crown on the selectivity and reaction rate was studied. Interaction of a sulfonated phosphine ligand with the crown was probed by NOESY-NNIR and utilisation of the crownether to serve as an anchor for catalyst immobilisation was investigated.
2005
690
23
5055
5065
REVIEWED