Complete asymmetric induction in [1, 2]-wittig rearrangement of a system involving a binaphthol moiety

Kiyooka, Syun‐ichi; Tsutsui, T.; Kira, Tomiko

doi:10.1016/s0040-4039(96)02080-1

Cited by 25 publications

(4 citation statements)

References 11 publications

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“…Thus, potassium has to occupy the outside allyl faces (Scheme 5, species 10). In agreement with substituent effects on the rearrangement rates, 15 we believe the aryl [1,2]-migration occurs by intramolecular nucleophilic substitution (passing through a spiro-6-oxa [5,2]octa-3,5dienide Meisenheimer complex 11; see Scheme 5) rather than by the radical cleavage/recombination sequence 16 governing the alkyl [1,2]-migration and postulated 17 for the mono-rearrangement of a structurally related allyl naphthyl ether. If the carbon-carbon linking obeys the inversion mode with respect to the location of the potassium atom (and the retention mode with respect to lithium), the first new stereocenter should have the (S) configuration when accompanied by (M) helicity and the (R) configuration when associated with a (P) axis.…”

supporting

confidence: 58%

Embedding an Allylmetal Dimer in a Chiral Cavity: The Unprecedented Stereoselectivity of a Twofold Wittig [1,2]-Rearrangement

Schlosser

Bailly

2006

J. Am. Chem. Soc.

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After alpha,alpha'-dimetalation, both 2,2'-diallyloxy-1,1'-binaphthyl and 2,2'-di-2-methylallyloxy-1,1'-binaphthyl undergo the Wittig rearrangement with perfect diastereoselectivity. When racemic 1,1'-binaphthyl-2,2'-diol ("BINOL") is used as the starting material, it gives rise to a 1:1 mixture of antipodal stereoisomers, whereas enantiomerically pure (M)-2,2'-diallyloxy-1,1'-binaphthyl affords (M)-(S,S)-1,1-(1,1'-binaphthyl-2,2'-diyl)bis(2-propen-1-ol) as the sole product. The (M)-(S,S)/(P)-(R,R) mixture resulting from the rearrangement of racemic 2,2'-diallyloxy-1,1'-binaphthyl can be effectively subjected to a kinetic racemate resolution by applying the Sharpless-Katsuki asymmetric epoxidation. The single-sided Wittig rearrangement of 2-allyloxy-2'-propyloxy-1,1'-binaphthyl proceeds without any diastereoselectivity as this substrate can only be monometalated and hence is incapable of intramolecular aggregate formation which is instrumental for the observed stereoselectivity.

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supporting

confidence: 58%

Embedding an Allylmetal Dimer in a Chiral Cavity: The Unprecedented Stereoselectivity of a Twofold Wittig [1,2]-Rearrangement

Schlosser

Bailly

2006

J. Am. Chem. Soc.

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“…In 2011, we reported a highly enantioselective construction of optically pure BINOL derivatives (Ar-BINMOLs) through neighboring-lithium-assisted [1,2]-Wittig rearrangement (NLAWR) (see eqs 1 and 2 in Scheme ), which generated a series of synthetically useful atropisomeric ligands with axial and sp 3 -central chirality. At this point, the NLAWR method displayed a remarkable FG tolerance compared with previous methods . Following this facile protocol, a family of structurally diverse Ar-BINMOLs and chiral amino alcohols were obtained in a straightforward manner with excellent enantioselectivities (≥99% ee) due to its perfect axial-to-central chirality transformation (eq 3 in Scheme ; >99% de in all cases) .…”

Section: The Discovery Of New Ligands With Multiple Stereogenic Cente...mentioning

confidence: 97%

The Discovery of Multifunctional Chiral P Ligands for the Catalytic Construction of Quaternary Carbon/Silicon and Multiple Stereogenic Centers

2020

Acc. Chem. Res.

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Conspectus The development of highly effective chiral ligands is a key topic in enhancing the catalytic activity and selectivity in metal-catalyzed asymmetric synthesis. Traditionally, the difficulty of ligand synthesis, insufficient accuracy in controlling the stereoselectivity, and poor universality of the systems often become obstacles in this field. Using the concept of nonequivalent coordination to the metal, our group has designed and synthesized a series of new chiral catalysts to access various carbon/silicon and/or multiple stereogenic centers containing products with excellent chemo-, diastereo-, and enantioselectivity. In this Account, we summarize a series of new phosphine ligands with multiple stereogenic centers that have been developed in our laboratory. These ligands exhibited good to excellent performance in the transition-metal-catalyzed enantioselective construction of quaternary carbon/silicon and multiple stereogenic centers. In the first section, notable examples of the design and synthesis of new chiral ligands by non-covalent interaction-based multisite activation are described. The integrations of axial chirality, atom-centered chirality, and chiral anions and multifunctional groups into a single scaffold are individually highlighted, as represented by Ar-BINMOLs and their derivative ligands, HZNU-Phos, Fei-Phos, and Xing-Phos. In the second, third, and fourth sections, the enantioselective construction of quaternary carbon stereocenters, multiple stereogenic centers, and silicon stereogenic centers using our newly developed chiral ligands is summarized. These sections refer to detailed reaction information in the chiral-ligand-controlled asymmetric catalysis based on the concept of nonequivalent coordination with multisite activation. Accordingly, a wide array of transition metal and main-group metal catalysts has been applied to the enantioselective synthesis of chiral heterocycles, amino acid derivatives, cyclic ketones, alkenes, and organosilicon compounds bearing one to five stereocenters. This Account shows that this new model of multifunctional ligand-controlled catalysts exhibits excellent stereocontrol and catalytic efficiency, especially in a stereodivergent and atom-economical fashion. Furthermore, a brief mechanistic understanding of the origin of enantioselectivity from our newly developed chiral catalyst systems could inspire further development of new ligands and enhancement of enantioselective synthesis by asymmetric metal catalysis.

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“…Despite several synthetic methods having been proposed for the synthesis of BINOL‐derived atropisomers bearing both axial and sp 3 central chirality in the last decade, some of these still suffer from drawbacks, such as tedious procedures, low yields, multiple steps, or the need for expensive chemicals or additional chiral sources. In spite of the limited success in the one‐step stereoselective synthesis of enantiomerically pure BINOL derivatives with axial and sp 3 central chirality, it is of particular value for the development of perfect diastereoselectivity through the axial‐to‐central chirality transfer or diastereoselective induction. Hence, the development of new methodologies for the stereoselective construction of BINOL‐derived atropisomers bearing both axial and sp 3 central chirality that can simultaneously address these issues was quite desirable.…”

Section: The Stereoselective Synthesis Of Ar‐binmols With Axial and Smentioning

confidence: 99%

Development of Ar‐BINMOL‐Derived Atropisomeric Ligands with Matched Axial and sp³ Central Chirality for Catalytic Asymmetric Transformations

2015

The Chemical Record

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Recently, academic chemists have renewed their interest in the development of 1,1'-binaphthalene-2,2'-diol (BINOL)-derived chiral ligands. Six years ago, a working hypothesis, that the chirality matching of hybrid chirality on a ligand could probably lead to high levels of stereoselective induction, prompted us to use the axial chirality of BINOL derivatives to generate new stereogenic centers within the same molecule with high stereoselectivity, obtaining as a result sterically favorable ligands for applications in asymmetric catalysis. This Personal Account describes our laboratory's efforts toward the development of a novel class of BINOL-derived atropisomers bearing both axial and sp(3) central chirality, the so-called Ar-BINMOLs, for asymmetric synthesis. Furthermore, on the basis of the successful application of Ar-BINMOLs and their derivatives in asymmetric catalysis, the search for highly efficient and enantioselective processes also compelled us to give special attention to the BINOL-derived multifunctional ligands with multiple stereogenic centers for use in catalytic asymmetric reactions.

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Complete asymmetric induction in [1, 2]-wittig rearrangement of a system involving a binaphthol moiety

Cited by 25 publications

References 11 publications

Embedding an Allylmetal Dimer in a Chiral Cavity: The Unprecedented Stereoselectivity of a Twofold Wittig [1,2]-Rearrangement

Embedding an Allylmetal Dimer in a Chiral Cavity: The Unprecedented Stereoselectivity of a Twofold Wittig [1,2]-Rearrangement

The Discovery of Multifunctional Chiral P Ligands for the Catalytic Construction of Quaternary Carbon/Silicon and Multiple Stereogenic Centers

Development of Ar‐BINMOL‐Derived Atropisomeric Ligands with Matched Axial and sp³ Central Chirality for Catalytic Asymmetric Transformations

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Complete asymmetric induction in [1, 2]-wittig rearrangement of a system involving a binaphthol moiety

Cited by 25 publications

References 11 publications

Embedding an Allylmetal Dimer in a Chiral Cavity: The Unprecedented Stereoselectivity of a Twofold Wittig [1,2]-Rearrangement

Embedding an Allylmetal Dimer in a Chiral Cavity: The Unprecedented Stereoselectivity of a Twofold Wittig [1,2]-Rearrangement

The Discovery of Multifunctional Chiral P Ligands for the Catalytic Construction of Quaternary Carbon/Silicon and Multiple Stereogenic Centers

Development of Ar‐BINMOL‐Derived Atropisomeric Ligands with Matched Axial and sp3 Central Chirality for Catalytic Asymmetric Transformations

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Development of Ar‐BINMOL‐Derived Atropisomeric Ligands with Matched Axial and sp³ Central Chirality for Catalytic Asymmetric Transformations