Directed ortho-C-H Silylation Coupled with trans-Selective Hydrogenation of Arylalkynes Catalyzed by Ruthenium Complexes of a Xanthene-Based Si,O,Si-Chelate Ligand, "xantsil"

Takashi Komuro, Takeo Kitano, Nobukazu Yamahira, Keisuke Ohta, Satoshi Okawara, Nathalie Mager, Masaaki Okazaki, Hiromi Tobita

Research output: Contribution to journalArticlepeer-review

11 Citations (Scopus)

Abstract

Ruthenium complexes bearing a xanthene-based bis(silyl) chelate ligand, "xantsil" ((9,9-dimethylxanthene-4,5-diyl)bis(dimethylsilyl)), Ru{κ3(Si,O,Si)-xantsil}(CO)(PR3) (1-Cy: R = Cy (cyclohexyl), 1-Cyp: R = Cyp (cyclopentyl)), were found to catalyze the reactions of internal arylalkynes with tertiary silanes (1-1.3 equiv) at a moderate temperature (room temperature to 70°C) to give (E)-alkenes having an ortho-silylated aryl group, i.e., (E)-R1C(H)=C(H)(C6H3-o-SiR33-p-R2). These catalytic reactions involve a unique ortho-selective C-H silylation of an aryl group in arylalkynes accompanied by hydrogenation of their C-C triple bonds (ortho-C-H silylation/hydrogenation). Importantly, in these reactions, the alkynyl moiety of arylalkynes serves as both a directing group and a hydrogen acceptor. The substrate scope of this ortho-C-H silylation/hydrogenation was explored by use of eight combinations of arylalkynes and tertiary silanes. In cases using bulky substrates, the catalytic performance of 1-Cyp with a relatively less bulky phosphine ligand (PCyp3) was shown to be superior to that of the PCy3 analogue 1-Cy.

Original languageEnglish
Pages (from-to)1209-1217
Number of pages9
JournalOrganometallics
Volume35
Issue number9
DOIs
Publication statusPublished - 2016 May 9

ASJC Scopus subject areas

  • Physical and Theoretical Chemistry
  • Organic Chemistry
  • Inorganic Chemistry

Fingerprint Dive into the research topics of 'Directed ortho-C-H Silylation Coupled with trans-Selective Hydrogenation of Arylalkynes Catalyzed by Ruthenium Complexes of a Xanthene-Based Si,O,Si-Chelate Ligand, "xantsil"'. Together they form a unique fingerprint.

Cite this