Spontaneous resolution of Δ and Λ enantiomeric pair of [Ru(phen)(bpy)2](PF6)2 (phen = 1,10-phenanthroline, bpy = 2,2′-bipyridine) by conglomerate crystallization

Spontaneous resolution is achieved for the Δ and Λ enantiomeric pair of ruthenium(II) complexes obtained by conglomerate crystallization from alcohol–water solutions, which is uncommon for six-coordinate Ru(II) complexes. The enantiomerically pure crystals pack into the chiral P41 and P43 space groups, respectively. A ligand exchange reaction is found between phen and bpy ligands for these Ru(II) complexes, but racemization is accompanied which has been proved by the single-crystal structure of the product. To extend this research, other counterion (BF4-) and bidentate ligand 4,4′-dimethyl-2,2′-bipyridine (dmbpy) are utilized to synthesize similar six-coordinate Ru(II) complexes. Nevertheless, conglomerate crystallization could not be realized in these two cases.

Graphical abstractSpontaneous resolution is achieved for the Δ and Λ enantiomeric pair of ruthenium(II) complexes obtained by conglomerate crystallization from alcohol–water solutions, which is uncommon for six-coordinate Ru(II) complexes. The enantiomerically pure crystals pack into the chiral P41 and P43 space groups, respectively. A ligand exchange reaction is found between phen and bpy ligands for these Ru(II) complexes, but racemization is accompanied which has been proved by the single-crystal structure of the product.Figure optionsDownload full-size imageDownload as PowerPoint slide