title: Synthesis of monodentate chiral spiro phosphonites and the electronic effect of ligand in asymmetric hydrogenation.
abstract: New monodentate chiral phosphonites were synthesized from enantiomerically pure 1,1'-spirobiindane-7,7'-diol. The phosphonites 2 were efficient ligands for the Rh-catalyzed asymmetric hydrogenation of alpha- and beta-dehydroamino acid derivatives, providing the amino acids in high enantioselectivities. The study of electronic effect showed that the electron-withdrawing substitutent on the P-phenyl ring of the phosphonite ligand dramatically decreased both the reactivity and enantioselectivity of the ligand.
authors.affiliation: State Key Laboratory and Institute of Elemento-organic Chemistry, Nankai University, Tianjin 300071, China.
authors.forename: Yu
authors.initials: Y
authors.lastname: Fu
authors.forename: Guo-Hua
authors.initials: GH
authors.lastname: Hou
authors.forename: Jian-Hua
authors.initials: JH
authors.lastname: Xie
authors.forename: Liang
authors.initials: L
authors.lastname: Xing
authors.forename: Li-Xin
authors.initials: LX
authors.lastname: Wang
authors.forename: Qi-Lin
authors.initials: QL
authors.lastname: Zhou