title: Construction of a Chiral Silicon Center by Rhodium-Catalyzed Enantioselective Intramolecular Hydrosilylation.
abstract: Rhodium-catalyzed enantioselective desymmetrizing intramolecular hydrosilylation of symmetrically disubstituted hydrosilanes is described. The original axially chiral phenanthroline ligand (S)-BinThro (Binol-derived phenanthroline) was found to work as an effective chiral catalyst for this transformation. A chiral silicon stereogenic center is one of the chiral motifs gaining much attention in asymmetric syntheses and the present protocol provides cyclic five-membered organosilanes incorporating chiral silicon centers with high enantioselectivities (up to 91 % ee). The putative active Rh(I) catalyst takes the form of an N,N,O-tridentate coordination complex, as determined by several complementary experiments.
authors.affiliation: Department of Applied Chemistry, Graduate School of Engineering, Nagoya University, Chikusa, Nagoya 464-8603 (Japan). yuki.n@apchem.nagoya-u.ac.jp.
authors.forename: Yuki
authors.initials: Y
authors.lastname: Naganawa
authors.affiliation: Department of Applied Chemistry, Graduate School of Engineering, Nagoya University, Chikusa, Nagoya 464-8603 (Japan).
authors.forename: Tomoya
authors.initials: T
authors.lastname: Namba
authors.affiliation: Department of Applied Chemistry, Graduate School of Engineering, Nagoya University, Chikusa, Nagoya 464-8603 (Japan).
authors.forename: Mayu
authors.initials: M
authors.lastname: Kawagishi
authors.affiliation: Department of Applied Chemistry, Graduate School of Engineering, Nagoya University, Chikusa, Nagoya 464-8603 (Japan). hnishi@apchem.nagoya-u.ac.jp.
authors.forename: Hisao
authors.initials: H
authors.lastname: Nishiyama
keywords: asymmetric catalysis; desymmetrization; hydrosilylation; rhodium; silicon