Showing papers by "Hiroaki Sasai published in 2016"
TL;DR: An efficient and enantioselective synthesis of oxa[9]helicenes has been established via vanadium(V)-catalyzed oxidative coupling/intramolecular cyclization of polycyclic phenols with good yields with up to 94% ee.
Abstract: An efficient and enantioselective synthesis of oxa[9]helicenes has been established via vanadium(V)-catalyzed oxidative coupling/intramolecular cyclization of polycyclic phenols. A newly developed vanadium complex cooperatively functions as both a redox and Lewis acid catalyst to promote the present sequential reaction and afford oxa[9]helicenes in good yields with up to 94% ee.
84 citations
TL;DR: An enantioselective addition of thiols and alcohols to aza-ortho-quinone methides, starting from diaryl methanols, was developed and furnished the corresponding adducts with excellent yields and enantiOSElectivities.
Abstract: An enantioselective addition of thiols and alcohols to aza-ortho-quinone methides, starting from diaryl methanols, was developed. The asymmetric additions occur under mild reaction conditions in the presence of chiral phosphoric acids and furnish the corresponding adducts with excellent yields and enantioselectivities.
56 citations
TL;DR: Shiabatsu et al. as discussed by the authors presented a list of distinguished scientific accomplishments in the field of asymmetric catalysis with particular emphasis on multimetallic cooperative catalysis, including the discovery of a rare earth metal, alkaline metals, and 1,1′-binaphthyl-2-binophthols (BINOLs).
Abstract: Professor Masakatsu Shibasaki’s distinguished scientific accomplishments in the field of asymmetric catalysis are compiled here with particular emphasis on multimetallic cooperative catalysis. In 1992, he discovered revolutionary multimetallic chiral complexes composed of a rare earth metal, alkaline metals, and 1,1′-binaphthyl-2-binaphthols (BINOLs) that promoted a number of enantioselective reactions in a highly efficient and stereoselective manner. This finding resulted in chiral multimetallic catalysts that have significantly advanced the field of enantioselective catalysis.
32 citations
TL;DR: In this article, an enantioselektive addition of Thiolen and Alkoholen an Aza-ortho-chinonmethide ausgehend von Diarylmethanolen wurde entwickelt.
Abstract: Eine enantioselektive Addition von Thiolen und Alkoholen an Aza-ortho-chinonmethide ausgehend von Diarylmethanolen wurde entwickelt. Die asymmetrischen Additionen verlaufen unter milden Reaktionsbedingungen in Anwesenheit chiraler Phosphorsauren und ergeben die entsprechenden Addukte mit exzellenten Ausbeuten und Enantioselektivitaten.
20 citations
TL;DR: The present imidazoline catalysis produced oxaziridines bearing a tetrasubstituted carbon stereogenic center in high yields with up to 87% ee.
Abstract: C 3-Symmetric chiral trisimidazolines with m-chloroperbenzoic acid promoted the organocatalytic oxidation of N-sulfonyl ketimine. The present imidazoline catalysis produced oxaziridines bearing a tetrasubstituted carbon stereogenic center in high yields with up to 87% ee.
11 citations
16 Oct 2016
TL;DR: First β-ICD-catalyzed [4+2] annulation affording functionalized enantioenriched 2H-pyran derivatives bearing a chiral all-carbon quaternary center is reported.
Abstract: A stereoselective [4+2] annulation of acyclic all-carbon tetrasubstituted alkenes with allenoates was described. The reaction with DABCO proceeded smoothly leading to the formation of highly functionalized 4H-pyran derivatives in good yields. We have also reported first β-ICD-catalyzed [4+2] annulation affording functionalized enantioenriched 2H-pyran derivatives bearing a chiral all-carbon quaternary center.
9 citations
TL;DR: Based on a tandem oxidation/aldol condensation reaction meso-1,4-tetralinediol is efficiently converted according to the title reaction as mentioned in this paper, which is the same as our method.
Abstract: Based on a tandem oxidation/aldol condensation reaction meso-1,4-tetralinediol is efficiently converted according to the title reaction.