The lactone concept—a novel approach to the metal-assisted atroposelective construction of axially chiral biaryl systems

Bringmann, Gerhard; Breuning, Matthias; Pfeifer, Robert‐Michael; Schenk, Wolfdieter A.; Kamikawa, Ken; Uemura, Mamoru

doi:10.1016/s0022-328x(02)01804-1

“…[20,21] This method involves the introduction of an ester bridge between the coupling partners, a subsequent intramolecular coupling reaction and resolution via a selective lactone cleavage step to afford the desired atropisomer. In some cases, interconversion between the lactone atropisomers facilitates dynamic kinetic resolution and allows for yields above 50% (Scheme 2).…”

Section: Introductionmentioning

confidence: 99%

The Application of Molecular Tethers in Controlling Axial Chirality

O`Sullivan¹

2016

MROC

View full text Add to dashboard Cite

Type of publicationArticle (peer-reviewed) Abstract: Atropisomeric biaryl compounds are an attractive target in organic chemistry due to their abundance in nature and their utility as ligands in catalysis. Among the methods available for their synthesis, the use of chiral tethers offers very high levels of stereocontrol. In this article, we review the application of molecular tethers in controlling axial chirality across a range of different ligands and natural products.

show abstract

“…[2,3] Stimulated by the continually growing demand for axially chiral biaryl compounds, [1,2] much attention has focused on the exploration of novel asymmetric methods.T wo traditional approaches, that is,the optical resolution of racemic materials and chiralauxiliary-based diastereoselective synthesis,are still restricted to the use of as toichiometric amount of chiral reagents. To our knowledge,o nly ah andful of catalytic strategies have been disclosed, [4,5] such as asymmetric CÀCcoupling, [5i,j] asymmetric construction of an aromatic ring, [5b,c,d,l,t] and atroposelective transformations of prostereogenic biaryls. To our knowledge,o nly ah andful of catalytic strategies have been disclosed, [4,5] such as asymmetric CÀCcoupling, [5i,j] asymmetric construction of an aromatic ring, [5b,c,d,l,t] and atroposelective transformations of prostereogenic biaryls.…”

mentioning

confidence: 99%

“…[4] Catalysis seems to be an ideal solution to this problem. To our knowledge,o nly ah andful of catalytic strategies have been disclosed, [4,5] such as asymmetric CÀCcoupling, [5i,j] asymmetric construction of an aromatic ring, [5b,c,d,l,t] and atroposelective transformations of prostereogenic biaryls. [1a] Despite these achievements,t he rapid construction of axially chiral biaryl compounds in ah ighly atropoenantioselective fashion is still in its infancy.…”

mentioning

confidence: 99%

Atropoenantioselective Redox‐Neutral Amination of Biaryl Compounds through Borrowing Hydrogen and Dynamic Kinetic Resolution

Zhang

¹

,

Wang

²

2017

View full text Add to dashboard Cite

We report herein a novel atropoenantioselective redox-neutral amination of biaryl compounds triggered by a cascade of borrowing hydrogen and dynamic kinetic resolution under the cooperative catalysis of a chiral iridium complex and an achiral Brønsted acid. This protocol features broad substrate scope and good functional-group tolerance, and allows the rapid assembly of axially chiral biaryl compounds in good to high yields and with high to excellent enantioselectivity.

show abstract

“…[4] Catalysis seems to be an ideal solution to this problem. To our knowledge,o nly ah andful of catalytic strategies have been disclosed, [4,5] such as asymmetric CÀCcoupling, [5i,j] asymmetric construction of an aromatic ring, [5b,c,d,l,t] and atroposelective transformations of prostereogenic biaryls. [1a] Despite these achievements,t he rapid construction of axially chiral biaryl compounds in ah ighly atropoenantioselective fashion is still in its infancy.In the 2000s,B ringmann and co-workers reported ar emarkable "bridged biaryl lactone" system to make biaryl molecules.…”

mentioning

confidence: 99%

Atropoenantioselective Redox‐Neutral Amination of Biaryl Compounds through Borrowing Hydrogen and Dynamic Kinetic Resolution

Wang

¹

,

Zhang

²

2017

View full text Add to dashboard Cite

We report herein an ovel atropoenantioselective redox-neutral amination of biaryl compounds triggered by ac ascade of borrowing hydrogen and dynamic kinetic resolution under the cooperative catalysis of ac hiral iridium complex and an achiral Brønsted acid. This protocol features broad substrate scope and good functional-group tolerance, and allows the rapid assembly of axially chiral biaryl compounds in good to high yields and with high to excellent enantioselectivity.Because of their unique molecular architectures and conformational behavior, [1] axially chiral biaryl molecules are of interest for potential applications in organic chemistry,d rug discovery,a nd material sciences. [2] In asymmetric catalysis, axially chiral biaryl structures,asexamplified by BINOL and BINAP,h ave served as privileged scaffolds for the development of chiral ligands,catalysts,and auxiliaries. [2,3] Stimulated by the continually growing demand for axially chiral biaryl compounds, [1,2] much attention has focused on the exploration of novel asymmetric methods.T wo traditional approaches, that is,the optical resolution of racemic materials and chiralauxiliary-based diastereoselective synthesis,are still restricted to the use of as toichiometric amount of chiral reagents. [4] Catalysis seems to be an ideal solution to this problem. To our knowledge,o nly ah andful of catalytic strategies have been disclosed, [4,5] such as asymmetric CÀCcoupling, [5i,j] asymmetric construction of an aromatic ring, [5b,c,d,l,t] and atroposelective transformations of prostereogenic biaryls. [1a] Despite these achievements,t he rapid construction of axially chiral biaryl compounds in ah ighly atropoenantioselective fashion is still in its infancy.In the 2000s,B ringmann and co-workers reported ar emarkable "bridged biaryl lactone" system to make biaryl molecules. [1a, 6] Thew orking hypothesis depends upon the stereoselective cleavage of configurationally stable bridged biaryl lactones by ac hiral nucleophile present in excess. Dynamic kinetic resolution (DKR), [7] relying on the interconversion of two lactone-bridged atropoisomers (Figure 1a, a-1 and a-2), enables the construction of axially chiral biaryl compounds in ah ighly enantio-and diastereoselective fashion. Later, enhanced studies of catalytic atropoenantioselective transformations of axially prostereogenic lactones were disclosed by the research groups of Yamada [8] and Wang. [9] Figure 1. Atropoisomerisation of bridged biaryl systems and strategies in the synthesis of axially chiral biaryls.

show abstract

The lactone concept—a novel approach to the metal-assisted atroposelective construction of axially chiral biaryl systems

Cited by 95 publications

References 106 publications

The Application of Molecular Tethers in Controlling Axial Chirality

The Application of Molecular Tethers in Controlling Axial Chirality

Atropoenantioselective Redox‐Neutral Amination of Biaryl Compounds through Borrowing Hydrogen and Dynamic Kinetic Resolution

Atropoenantioselective Redox‐Neutral Amination of Biaryl Compounds through Borrowing Hydrogen and Dynamic Kinetic Resolution

Contact Info

Product

Resources

About