Organocatalytic Atroposelective Synthesis of N−N Axially Chiral Indoles and Pyrroles by De Novo Ring Formation

Angewandte Chemie International Edition, Journal Year: 2022, Volume and Issue: 61(17)

Published: Jan. 26, 2022

Abstract The first highly atroposelective construction of N−N axially chiral indole scaffolds was established via a new strategy de novo ring formation. This makes use the organocatalytic asymmetric Paal–Knorr reaction well‐designed N ‐aminoindoles with 1,4‐diketones, thus affording ‐pyrrolylindoles in high yields and excellent atroposelectivities (up to 98 % yield, 96 ee). In addition, this is applicable for synthesis bispyrroles 97 More importantly, such heterocycles can be converted into organocatalysts applications catalysis, some molecules display potent anticancer activity. work not only provides but also offers members atropisomer family promising synthetic medicinal chemistry.

Language: Английский

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Carbene-catalyzed atroposelective synthesis of axially chiral styrenes

Nature Communications, Journal Year: 2022, Volume and Issue: 13(1)

Published: Jan. 10, 2022

Abstract Axially chiral styrenes bearing a axis between sterically non-congested acyclic alkene and an aryl ring are difficult to prepare due low rotational barrier of the axis. Disclosed here is N -heterocyclic carbene (NHC) catalytic asymmetric solution this problem. Our reaction involves ynals, sulfinic acids, phenols as substrates with NHC catalyst. Key steps involve selective 1,4-addition anion acetylenic acylazolium intermediate sequential E -selective protonation set up affords axially product > 99:1 e.r ., 20:1 / Z selectivity, excellent yields. The sulfone carboxylic ester moieties in our styrene products common bioactive molecules catalysis.

Language: Английский

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Axially chiral alkenes: Atroposelective synthesis and applications

Tetrahedron Chem, Journal Year: 2022, Volume and Issue: 1, P. 100009 - 100009

Published: March 1, 2022

Axial chirality is historically epitomized by biaryl compounds containing rotationally impeded aryl-aryl linkage. As the field of atroposelective catalysis advances, synthesis and application less common scaffolds such as alkenes have now come to fore. The manifestation axial in aryl was hypothesized 1928 first resolution achieved nearly a decade later. However, catalytic asymmetric construction axially chiral open-chain appeared only 2017 which ushered renewed focus on these structures. In principle, possess an alkene group tethered at one end stereogenic axis, greatly reduces overall rigidity. To date, atropisomers with C (vinyl)-C (aryl) (vinyl)-heteroatom bond been reported. Considering rapid growth synthetic utility alkenes, this review intends provide historical overview discusses new developments. It hope that timely discussion would motivate continued nascent field.

Language: Английский

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Synthesis of axially chiral alkenylboronates through combined copper- and palladium-catalysed atroposelective arylboration of alkynes

Nature Synthesis, Journal Year: 2023, Volume and Issue: 2(2), P. 140 - 151

Published: Jan. 5, 2023

Language: Английский

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Enantioselective Access to Triaryl-2-pyrones with Monoaxial or Contiguous C–C Diaxes via Oxidative NHC Catalysis

ACS Catalysis, Journal Year: 2023, Volume and Issue: 13(4), P. 2565 - 2575

Published: Feb. 6, 2023

We present herein an unprecedented stereoselective synthesis of triaryl-2-pyrones with monoaxial or contiguous diaxes from readily available starting materials. This N-heterocyclic carbene catalysis method adopts atroposelective annulation 2-aryketones ynals under oxidative conditions. The includes the construction one two axes in a single operation, achieves step economy, and affords axially chiral moderate to good yields, high excellent enantioselectivities. DFT calculations relative energies stereoisomers rotational barriers were performed.

Language: Английский

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Transition-metal-catalyzed atroposelective synthesis of axially chiral styrenes

Chemical Communications, Journal Year: 2023, Volume and Issue: 59(85), P. 12669 - 12684

Published: Jan. 1, 2023

Recent advances in the asymmetric synthesis of axially chiral styrenes catalyzed by transition metals were summarized.

Language: Английский

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Photocatalytic Z/E isomerization unlocking the stereodivergent construction of axially chiral alkene frameworks

Nature Communications, Journal Year: 2024, Volume and Issue: 15(1)

Published: April 16, 2024

Abstract The past century has witnessed a large number of reports on the Z / E isomerization alkenes. However, vast majority them are still limited to di- and tri-substituted stereospecific tetrasubstituted alkenes remains be an underdeveloped area, thus lacking in stereodivergent synthesis axially chiral Herein we report atroposelective alkene analogues by asymmetric allylic substitution-isomerization, followed their via triplet energy transfer photocatalysis. In this regard, N -vinylquinolinones is achieved efficiently. Mechanistic studies indicate that benzylic radical generation distribution two key factors for preserving enantioselectivities compounds.

Language: Английский

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Rhodium‐Catalyzed Atroposelective Access to Axially Chiral Olefins via C−H Bond Activation and Directing Group Migration

Angewandte Chemie International Edition, Journal Year: 2021, Volume and Issue: 61(1)

Published: Oct. 22, 2021

Axially chiral open-chain olefins represent an underexplored class of platform. In this report, two classes tetrasubstituted axially acyclic have been accessed in excellent enantioselectivity and regioselectivity via C-H activation (hetero)arenes assisted by a migratable directing group en route to coupling with sterically hindered alkynes. The indoles bearing N-aminocarbonyl afforded C-N acrylamides the assistance racemic zinc carboxylate additive. DFT studies suggest β-nitrogen elimination-reinsertion pathway for migration. Meanwhile, employment N-phenoxycarboxamide delivered C-C enamides migration oxidizing group. Experiments that both cases (hetero)arene substrate adopts well-defined orientation during activation, which turn determines disposition alkyne migratory insertion. Synthetic applications representative are demonstrated.

Language: Английский

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Rational Design of Axially Chiral Styrene‐Based Organocatalysts and Their Application in Catalytic Asymmetric (2+4) Cyclizations

Angewandte Chemie International Edition, Journal Year: 2021, Volume and Issue: 61(7)

Published: Nov. 30, 2021

A new class of axially chiral styrene-based thiourea tertiary amine catalysts, which have unique characteristics such as an efficient synthetic route, multiple elements, and activating groups, has been rationally designed. These catalysts proven to be organocatalysts, enabling the chemo-, diastereo-, enantioselective (2+4) cyclization 2-benzothiazolimines with homophthalic anhydrides in good yields (up 96 %) excellent stereoselectivities (all >95:5 dr, up 98 % ee). More importantly, theoretical calculations elucidated important role styrene moiety controlling both reactivity enantioselectivity. This work not only represents first design catalytic asymmetric 2-benzothiazolimines, but also gives in-depth understanding organocatalysts.

Language: Английский

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Recent advances in the catalytic asymmetric construction of atropisomers by central-to-axial chirality transfer

Organic Chemistry Frontiers, Journal Year: 2022, Volume and Issue: 9(8), P. 2280 - 2292

Published: Jan. 1, 2022

We highlighted the recent advances in field of central-to-axial chirality transfer for synthesis axially chiral molecules.

Language: Английский

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