title: Highly E-Selective and Enantioselective Michael Addition to Electron-Deficient Internal Alkynes Under Chiral Iminophosphorane Catalysis.
abstract: A highly E-selective and enantioselective conjugate addition of 2-benzyloxythiazol-5(4H)-ones to β-substituted alkynyl N-acyl pyrazoles is achieved under the catalysis of a P-spiro chiral iminophosphorane. Simultaneous control of the newly generated central chirality and olefin geometry is possible with a wide array of the alkynyl Michael acceptors possessing different aromatic and aliphatic β-substituents, as well as the various α-amino acid-derived thiazolone nucleophiles. This protocol provides access to structurally diverse, optically active α-amino acids bearing a geometrically defined trisubstituted olefinic component at the α-position.
authors.affiliation: Institute of Transformative Bio-Molecules (WPI-ITbM) and Department of Applied Chemistry, Graduate School of Engineering, Nagoya University, Nagoya 464-8603 (Japan).
authors.forename: Daisuke
authors.initials: D
authors.lastname: Uraguchi
authors.affiliation: Institute of Transformative Bio-Molecules (WPI-ITbM) and Department of Applied Chemistry, Graduate School of Engineering, Nagoya University, Nagoya 464-8603 (Japan).
authors.forename: Kohei
authors.initials: K
authors.lastname: Yamada
authors.affiliation: Institute of Transformative Bio-Molecules (WPI-ITbM) and Department of Applied Chemistry, Graduate School of Engineering, Nagoya University, Nagoya 464-8603 (Japan). tooi@apchem.nagoya-u.ac.jp.|CREST, Japan Science and Technology Agency (JST), Nagoya University, Nagoya 464-8603 (Japan). tooi@apchem.nagoya-u.ac.jp.
authors.forename: Takashi
authors.initials: T
authors.lastname: Ooi
mesh_terms: D000475:Alkenes / Q000737:chemistry; D000480:Alkynes / Q000737:chemistry*; D000596:Amino Acids / Q000737:chemistry; D002384:Catalysis; D004583:Electrons; D015394:Molecular Structure; D010753:Phosphoranes / Q000737:chemistry*; D013237:Stereoisomerism
chemical_list: D000475:Alkenes; D000480:Alkynes; D000596:Amino Acids; D010753:Phosphoranes
keywords: Michael addition; amino acids; asymmetric catalysis; organocatalysis; synthetic methods