Diastereotopic relationship between planar and central chiralities in the formation of Ru(η 3-allyl)(CO)(PPh 3)(L–L ′) complexes

Abstract

Hydride ruthenium complexes, RuHCl(CO)(PPh 3) 2(L–L ′) 3 (L–L ′=bidentate ligand having nitrogen and oxygen) react with allenes to give Ru(η 3-allyl)(CO)(PPh 3)(L–L ′) complexes 5 in good yields via hydrometalation reaction. The complexes 5 have planar chirality at the η 3-allyl ligand and central chirality at the Ru metal, and consist of one pair of enantiomers. Ligand substitution reaction of Ru(η 3-allyl)Cl(CO)(PPh 3) 2 complexes 6 with bidentate ligands (L–L ′) also afford the complexes 5 which have the same stereochemistry as those formed by the hydrometalation reaction. The planar chirality is controlled by the central chirality at the Ru metal in both the formations of the complexes 5. The structure of 5a (L–L ′=N–N bidentate ligand) was determined by the X-ray crystal structure analysis.