Stereoselective Synthesis of Polysubstituted Conjugated Dienes Enabled by Photo‐Driven Sequential Sigmatropic Rearrangement

Angewandte Chemie International Edition, Год журнала: 2024, Номер 63(24)

Опубликована: Апрель 8, 2024

We here reported a highly stereoselective method for the synthesis of polysubstituted conjugated dienes from α-aryl α-diazo alkynyl ketones and pyrazole-substituted unsymmetric aminals under mild conditions, which was promoted by photo-irridation involved with 1,6-dipolar intermediate quadruple sigmatropic rearrangements, successfully developed. In this transformation, cleavage four bonds recombination five were implemented in one operational step. This protocol provided modular tool constructing amines, pyrazoles α-alkynyl-α-diazoketones one-pot manner. The results mechanistic investigation indicated that plausible reaction path underwent 1,6-sigmatropic rearrangement instead 1,5-sigmatropic rearrangement.

Язык: Английский

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Difluorocarbene-induced [1,2]- and [2,3]-Stevens rearrangement of tertiary amines

Nature Communications, Год журнала: 2024, Номер 15(1)

Опубликована: Июнь 5, 2024

The [1,2]- and [2,3]-Stevens rearrangements are one of the most fascinating chemical bond reorganization strategies in organic chemistry, they have been demonstrated a wide range applications, representing fundamental reaction tactic for synthesis nitrogen compounds community. However, their applicabilities limited by scarcity efficient, general, straightforward methods generating ammonium ylides. Herein, we report general difluorocarbene-induced tertiary amine-involved stemmed from situ generated difluoromethyl ylides, which allows versatile amines bearing either allyl, benzyl, or propargyl groups, resulting corresponding products under same conditions with way. Broad substrate scope, simple operation, mild late-stage modification natural highlight advantages this strategy, meanwhile, rearrangement is believed to bring opportunities transformations ylides assembly valuable amino acids. This will further enrich repertoire difluorocarbene species, facilitate development reactions involving salts, provide an avenue type reactions.

Язык: Английский

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Brønsted acid–catalyzed asymmetric dearomatization for synthesis of chiral fused polycyclic enone and indoline scaffolds

Science Advances, Год журнала: 2023, Номер 9(11)

Опубликована: Март 15, 2023

In the past two decades, substantial advances have been made on asymmetric alkyne functionalization by activation of inert alkynes. However, these transformations so far mostly limited to transition metal catalysis, and chiral Brønsted acid-catalyzed examples are rarely explored. Here, we report a dearomatization reaction phenol- indole-tethered homopropargyl amines, allowing practical atom-economical synthesis diverse array valuable fused polycyclic enones indolines bearing quaternary carbon stereocenter contiguous stereogenic centers in moderate good yields with excellent diastereoselectivities generally enantioselectivities (up >99% enantiomeric excess). This protocol demonstrates dearomatizations via vinylidene-quinone methides.

Язык: Английский

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Asymmetric formal C–C bond insertion into aldehydes via copper-catalyzed diyne cyclization

Nature Communications, Год журнала: 2023, Номер 14(1)

Опубликована: Ноя. 3, 2023

The formal C-C bond insertion into aldehydes is an attractive methodology for the assembly of homologated carbonyl compounds. However, homologation has been limited to diazo approach and enantioselective reaction was rarely developed. Herein, we report asymmetric through diyne cyclization strategy. In presence Cu(I)/SaBOX catalyst, this method leads efficient construction versatile axially chiral naphthylpyrroles in moderate excellent yields with good enantioselectivities. This protocol represents a rare example using non-diazo approach. combined experimental computational mechanistic studies reveal mechanism, origin regioselectivity stereoselectivity. Notably, phosphine ligand derived from synthesized skeleton proven be applicable catalysis.

Язык: Английский

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Copper-catalyzed enantioselective diyne cyclizationviaC(sp²)–O bond cleavage

Chemical Science, Год журнала: 2023, Номер 14(13), С. 3493 - 3500

Опубликована: Янв. 1, 2023

A copper-catalyzed asymmetric cascade cyclization via C(sp 2 )–O bond cleavage is disclosed, affording a range of chromeno[3,4- c ]pyrroles bearing triaryl oxa-quaternary carbon stereocenter in high yields and enantioselectivities.

Язык: Английский

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Asymmetric Catalytic Ring‐Expansion of 3‐Methyleneazetidines with α‐Diazo Pyrazoamides towards Proline‐Derivatives

Angewandte Chemie International Edition, Год журнала: 2023, Номер 62(32)

Опубликована: Июнь 15, 2023

We realized a highly efficient formal [1,2]-sigmatropic rearrangement of ammonium ylides generated from 3-methylene-azetidines and α-diazo pyrazoamides. The employ readily available chiral cobalt(II) complex N,N'-dioxide enabled the ring-expansion azetidines, affording variety quaternary prolineamide derivatives with excellent yield (up to 99 %) enantioselectivity % ee) under mild reaction condition. For ylides, installation pyrazoamide group as masked brick build scaffolds proved successful. enantioselective ring expansion process was elucidated by DFT calculations.

Язык: Английский

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Organocatalytic intramolecular (4 + 2) annulation of enals with ynamides: atroposelective synthesis of axially chiral 7-aryl indolines

Chemical Science, Год журнала: 2023, Номер 14(22), С. 5918 - 5924

Опубликована: Янв. 1, 2023

Catalytic enantioselective transformation of alkynes has become a powerful tool for the synthesis axially chiral molecules. Most these atroposelective reactions rely on transition-metal catalysis, and organocatalytic approaches are largely limited to special which act as precursors Michael acceptors. Herein, we disclose an intramolecular (4 + 2) annulation enals with ynamides. This method allows efficient highly atom-economical preparation various 7-aryl indolines in generally moderate good yields excellent enantioselectivities. Computational studies were carried out elucidate origins regioselectivity enantioselectivity. Furthermore, phosphine ligand derived from synthesized indoline was proven be potentially applicable asymmetric catalysis.

Язык: Английский

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Copper-catalyzed enantioselective desymmetrizing C(sp2)–H functionalization of azide-ynamides via α-imino copper carbenes

Science China Chemistry, Год журнала: 2024, Номер 67(9), С. 2982 - 2988

Опубликована: Июль 3, 2024

Язык: Английский

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Asymmetric one-carbon ring expansion of diverse N-heterocycles via copper-catalyzed diyne cyclization

Science Advances, Год журнала: 2024, Номер 10(41)

Опубликована: Окт. 9, 2024

One-carbon ring expansion reaction of N-heterocycles has gained particular attention in the past decade because this method allows for conversion readily available into potentially useful complex ring-expanded N-heterocycles, which are inaccessible by traditional methods. However, catalytic asymmetric variant been rarely reported to date. Herein, we disclose an enantioselective one-carbon through chiral copper-catalyzed diyne cyclization, leading practical, atom-economic and divergent assembly array valuable bearing a quaternary stereocenter generally good excellent yields with enantioselectivities (up >99% ee). This protocol represents first example based on alkynes.

Язык: Английский

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Copper-Catalyzed Triyne Cyclization via Vinyl Cations

Organic Letters, Год журнала: 2025, Номер unknown

Опубликована: Март 27, 2025

Herein, we describe an efficient copper-catalyzed cyclization of triynes via vinyl cation intermediates. The reaction leads to the practical and atom-economical synthesis valuable polycyclic pyrroles by constructing three new rings in one step under mild conditions. proposed mechanism shows ordered regioselective alkynes. Moreover, possibility such asymmetric triyne also emerges.

Язык: Английский

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