Arene ruthenium complexes with chiral Schiff bases derived from pyridine-2-carboxaldehyde or 2-acetylpyridine

Article abstract of DOI:10.1016/S0022-328X(97)00410-5

The Schiff bases (LL′) formed from pyridine-2-carboxaldehyde or 2-acetyl pyridine and S-1-phenylethylamine react with [Ru(mes)Cl₂]₂ (mes = η⁶-C₆H₃Me₃-1,3,5) to form diastereomeric salts [Ru(mes)Cl(LL′)][BF₄]. Crystallisation gives a single diastereomer, (S_RuS_C) in each case, which have been characterised by X-ray diffraction; the conformation of the phenylethyl group is different to related η⁶-benzene complexes. The configuration at the metal is solvent dependent, it is stable in CDCl₃ but epimerisation occurs in D₂O.