title: Synthesis, characterization and reactivity of tetranuclear ruthenium hydrido clusters containing chiral phosphine ligands.
abstract: The chiral clusters [H(4)Ru(4)(CO)(12-n)(L)(n)] (n = 1, 2; L = NMDPP), 1,1-[H(4)Ru(4)(CO)(10)(L-L)] (L-L = DUPHOS, DIPAMP), 1,2-[H(4)Ru(4)(CO)(10)(DIOP)] and [{H(4)Ru(4)(CO)(10)(DIOP)}(2)] have been synthesized by derivatizing the parent carbonyl cluster [H(4)Ru(4)(CO)(12)] with the appropriate mono- or didentate chiral phosphine ligand. The phosphine-substituted clusters were found to be able to catalyze the (asymmetric) hydrogenation of tiglic acid albeit with relatively low selectivity (enantiomeric excesses varying from 0 to 23%). It was found that the stability of the chiral ruthenium hydride clusters and the product distribution obtained in the catalytic reactions are dependent on the nature of the chiral phosphine. The crystal structures of [H(4)Ru(4)(CO)(12-n)(L)(n)] (n = 1, 2; L = NMDPP), 1,1-[H(4)Ru(4)(CO)(10)(L-L)] (L-L = DUPHOS, O-DUPHOS (partially oxygenated ligand), DIPAMP), 1,2-[H(4)Ru(4)(CO)(10)(DIOP)] and [{H(4)Ru(4)(CO)(10)(DIOP)}(2)] are presented.
authors.affiliation: Inorganic Chemistry, Center for Chemistry and Chemical Engineering, Lund University, Box 124, SE-221 00 Lund, Sweden.
authors.forename: Viktor
authors.initials: V
authors.lastname: Moberg
authors.forename: Pertti
authors.initials: P
authors.lastname: Homanen
authors.forename: Simona
authors.initials: S
authors.lastname: Selva
authors.forename: Roger
authors.initials: R
authors.lastname: Persson
authors.forename: Matti
authors.initials: M
authors.lastname: Haukka
authors.forename: Tapani A
authors.initials: TA
authors.lastname: Pakkanen
authors.forename: Magda
authors.initials: M
authors.lastname: Monari
authors.forename: Ebbe
authors.initials: E
authors.lastname: Nordlander