Enantioselective Cyanosilylation of Alkynyl Ketones Catalyzed by Combined Systems Consisting of Chiral Ruthenium(II) Complex and Lithium Phenoxide. Issue 7 (22nd February 2018)

• Record Type: Journal Article
• Authors: Ohkuma, Takeshi; Kurono, Nobuhito; Sakaguchi, Yusuke; Yamauchi, Kohei; Yurino, Taiga
• Is Part Of: Advanced synthesis & catalysis. Volume 360:Issue 7(2018)
• Page Start: 1517
• Page End: 1522
• Publication Date: 2018-02-22
• Subjects: alkynyl ketones -- asymmetric catalysis -- bimetallic catalysts -- cyanosilylation -- lithium -- ruthenium; Catalysis -- Periodicals; Organic compounds -- Synthesis -- Periodicals; Chemistry -- Periodicals; Chemistry, Technical -- Periodicals; Chemistry -- Periodicals; Catalysis -- Periodicals; Technology, Pharmaceutical -- Periodicals; 547.2
• DOI: 10.1002/adsc.201701593
• Languages: English
• ISSNs: 1615-4150

Abstract

Abstract: Asymmetric cyanosilylation of alkynyl ketones with the catalyst systems consisting of amino acid/2, 2′‐bis(diphenylphosphino)‐1, 1′‐binaphthyl (BINAP)/ruthenium(II) complex and lithium phenoxide (Ru⋅Li cat.) was studied. The reaction was conducted in tert ‐butyl methyl ether (TBME) at −78 °C with a substrate‐to‐catalyst molar ratio (S/C) as high as 2000. A series of simple and functionalized ketones was converted into the alkynyl tertiary cyanohydrin derivatives in up to 99% ee. Appropriate selection of an amino‐acid ligand of the catalyst according to the substrate structure was crucially important to achieve high enantioselectivity and a wide scope of substrates. Transformation of the chiral cyanohydrin product into a functionalized lactone was also examined. Abstract :