Enantioselective Synthesis of Spirosilabicyclohexenes by Asymmetric Dual Ring Expansion of Spirosilabicyclobutane with Alkynes

Angewandte Chemie International Edition, Journal Year: 2022, Volume and Issue: 61(48)

Published: Oct. 7, 2022

Silaspiranes have attracted particular attention due to their chiral spiro-silicon center, which serves as an ideal carbon isostere and can endow spiro-analogs with distinct properties. Distinct from previously reported cyclization or cycloaddition strategies form 5/5-silaspiranes, we report herein the asymmetric dual ring expansion of spirosilabicyclobutanes alkynes synthesize axially spirosilabicyclohexenes bearing a novel 6/6-silaspirane framework. DFT (density functional theory) calculations provide deep insight into origin high enantioselectivity controlled by sterically demanding binaphthyl phosphoramidite ligand. Preliminary studies chiroptical properties indicate that one spirosilabicyclohexene analogs exhibit fluorescence emission, Cotton effects CPL (circularly polarized luminescence) activity.

Language: Английский

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Maleimide‐Controlled Formation of Indanonylpyrrolinediones and Spiroindanonylpyrrolinediones via Rh(III)‐Catalyzed C−H Activation of Sulfoxonium Ylides

Advanced Synthesis & Catalysis, Journal Year: 2023, Volume and Issue: 365(24), P. 4595 - 4602

Published: Nov. 1, 2023

Abstract A substrate‐controlled [4+1] annulation of sulfoxonium ylides with maleimides via Rh(III)‐catalyzed C−H bond activation is developed. The reaction 2‐methyl‐ N ‐arylmaleimides in the presence AgNTf 2 diastereoselectively provides diversely functionalized indanonylpyrroline‐2,5‐dione derivatives. Furthermore, AgBF 4 , subsequent leads to biologically intriguing various spiroindanonylpyrroline‐2,5‐diones. This methodology offers a broad substrate scope, good functional group tolerance, and diastereoselectivity.

Language: Английский

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NHC-catalysed [3 + 2]-asymmetric annulation between pyrazolin-4,5-diones and enals: synthesis of novel spirocyclic pyrazolone γ-butyrolactones and computational study of mechanism and stereoselectivity

Organic Chemistry Frontiers, Journal Year: 2021, Volume and Issue: 9(2), P. 420 - 427

Published: Dec. 6, 2021

Herein we present the first asymmetric synthesis of spiropyrazolone γ-butyrolactones from 1 H -pyrazol-4,5-diones and enals by an NHC-catalysed [3 + 2] annulation. DFT calculations carried out predict experimental configuration final adducts.

Language: Английский

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Construction of C2‐Spirocyclopropyl‐Indolin‐3‐Ones through Base‐Promoted [2+1] Annulation Reaction of Indolin‐3‐ones with Bromosulfonium Salts

European Journal of Organic Chemistry, Journal Year: 2023, Volume and Issue: 26(15)

Published: March 15, 2023

Abstract A simple base‐promoted [2+1] annulation of indolin‐3‐ones and bromosulfonium salts has been developed in this article. This strategy uses easily prepared 1 as C1 synthons 2 C2 under mild reaction conditions, 33 examples C2‐spirocyclopropyl‐indolin‐3‐ones were obtained with up to 99 % yield >20 : dr.

Language: Английский

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Rhodium-Catalyzed Desymmetric Arylation of γ,γ-Disubsituted Cyclohexadienones: Asymmetric Synthesis of Chiral All-Carbon Quaternary Centers

Organic Letters, Journal Year: 2022, Volume and Issue: 24(7), P. 1556 - 1560

Published: Feb. 10, 2022

The desymmetric arylation of prochiral cyclohexadienones with ArZnCl in the presence an (R)-segphos–rhodium catalyst gave high yields corresponding cyclohexenones, which contain a chiral arylated carbon center at β-position and all-carbon quaternary γ-position, diastereo- enantioselectivities. This catalytic system was also applied to spirocarbocyclic afforded cyclohexenones bearing spiro dr ee.

Language: Английский

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Copper‐Initiated Radical Dearomative 2,5‐Alkylarylation of Furans via Trihalomethylation/Spirocyclization Cascade

Chinese Journal of Chemistry, Journal Year: 2022, Volume and Issue: 40(24), P. 2893 - 2899

Published: Sept. 7, 2022

Comprehensive Summary Here is an operable and rare strategy for copper‐initiated radical dearomative 2,5‐alkylarylation of furan. By means this strategy, we realized the dearomatization furans to construct spirooxindoles with good yield in one‐step via trihalomethylation/spirocyclization cascade progress.

Language: Английский

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Squaramide-catalysed asymmetric Michael addition/cyclization cascade reaction of 4-arylmethylidene-2,3-dioxopyrrolidines with 2-isothiocyanato-1-indanones

Organic & Biomolecular Chemistry, Journal Year: 2021, Volume and Issue: 19(33), P. 7181 - 7185

Published: Jan. 1, 2021

An efficient squaramide-catalysed asymmetric Michael/cyclization cascade reaction of 4-arylidene-2,3-dioxopyrrolidines with 2-isothiocyanato-1-indanones afforded indanone-derived spiropyrrolidones in excellent yields high stereoselectivities.

Language: Английский

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Tandem 1,6-addition/cyclopropanation/rearrangement reaction of vinylogous para-quinone methides with 3-chlorooxindoles: construction of vicinal quaternary carbon centers

Organic Chemistry Frontiers, Journal Year: 2022, Volume and Issue: 9(14), P. 3697 - 3708

Published: Jan. 1, 2022

A novel tandem 1,6-addition/cyclopropanation/rearrangement reaction of vinylogous para -quinone methides with 3-chlorooxindoles has been developed, providing dispirooxindole–cyclopentane–cyclohexadienones vicinal quaternary carbon centers.

Language: Английский

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Asymmetric Synthesis of Spirooxazolidinone Oxindoles by the Thiourea‐Catalyzed Aldol Reaction of 2‐Isocyanatomalonate Diesters

Advanced Synthesis & Catalysis, Journal Year: 2022, Volume and Issue: 364(12), P. 2067 - 2071

Published: May 6, 2022

Abstract A tertiary amino‐thiourea catalyzed asymmetric aldol reaction between 2‐isocyanatomalonate esters and isatins has been achieved. Optical active spirooxazolidinone oxindole derivatives could be obtained with excellent yields (80%–96%) enantioselectivities (67%–99% ee) under mild conditions, providing an updated example to apply as the electrophile in esters. magnified image

Language: Английский

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Enantioselective Synthesis of Spirosilabicyclohexenes by Asymmetric Dual Ring Expansion of Spirosilabicyclobutane with Alkynes

Angewandte Chemie, Journal Year: 2022, Volume and Issue: 134(48)

Published: Oct. 7, 2022

Abstract Silaspiranes have attracted particular attention due to their chiral spiro‐silicon center, which serves as an ideal carbon isostere and can endow spiro‐analogs with distinct properties. Distinct from previously reported cyclization or cycloaddition strategies form 5/5‐silaspiranes, we report herein the asymmetric dual ring expansion of spirosilabicyclobutanes alkynes synthesize axially spirosilabicyclohexenes bearing a novel 6/6‐silaspirane framework. DFT (density functional theory) calculations provide deep insight into origin high enantioselectivity controlled by sterically demanding binaphthyl phosphoramidite ligand. Preliminary studies chiroptical properties indicate that one spirosilabicyclohexene analogs exhibit fluorescence emission, Cotton effects CPL (circularly polarized luminescence) activity.

Language: Английский

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