Chiral Bidentate Phosphoramidite-Pd Catalyzed Asymmetric Decarboxylative Dipolar Cycloaddition for Multistereogenic Tetrahydrofurans with Cyclic N-Sulfonyl Ketimine Moieties

Organic Letters, Journal Year: 2021, Volume and Issue: 23(12), P. 4715 - 4720

Published: June 7, 2021

An asymmetric [3 + 2] cycloaddition of vinyl ethylenecarbonates (VECs) and (E)-3-arylvinyl substituted benzo[d] isothiazole 1,1-dioxides has been developed using the Pd complex a bidentate phosphoramidite (Me-BIPAM) as catalyst, providing wide variety chiral multistereogenic vinyltetrahydrofurans in good yields with excellent diastereo- enantioselectivities (up to >20:1 dr, 99% ee).

Language: Английский

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Palladium‐Catalyzed [4+2] and [6+2] Dipolar Cycloadditions for the Construction of Benzo[d]isothiazole 1,1‐Dioxide Fused 1,3‐Oxazinanes and 1,3‐Oxazocanes^†

Chinese Journal of Chemistry, Journal Year: 2023, Volume and Issue: 42(8), P. 829 - 834

Published: Dec. 8, 2023

Comprehensive Summary The Pd‐catalyzed dipolar cycloaddition represents a significant synthetic strategy for the construction of useful heterocyclic compounds. This study developed [4+2] and [6+2] reactions benzo[ d ]isothiazole 1,1‐dioxides (BDs) leading to synthesis BD‐fused 1,3‐oxazinane 1,3‐oxazocane derivatives, respectively. In particular, 1,3‐oxazinanes demonstrated regio‐ enantioselective characteristics, resulting in products with good yields, enantioselectivity regioselectivity (if applicable). Furthermore, reaction this work represented first medium‐sized ring compounds based on BDs.

Language: Английский

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Construction of nine-membered N,N,O-heterocycles via Pd-catalyzed [6+3] dipolar cycloaddition

Chemical Communications, Journal Year: 2022, Volume and Issue: 58(75), P. 10560 - 10563

Published: Jan. 1, 2022

A new approach for the synthesis of 9-membered N,N,O-heterocycles by Pd-catalyzed [6+3] dipolar cycloaddition N-iminoisoquinolinium ylides and 2-vinyl oxetanes has been developed. The scope this was demonstrated with 28 examples. This is another important synthetic strategy medium-sized rings employing as ternary synthons.

Language: Английский

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Preparation of Spirocyclic Vinylic Carbonates from Allylic Alcohols

Organic Letters, Journal Year: 2024, Volume and Issue: 26(3), P. 577 - 580

Published: Jan. 8, 2024

We present the synthesis of exo- and endo-spirovinylethylene carbonates, starting from various cyclic allylic alcohols. This one-pot cascade reaction to spirocyclic scaffold was optimized using a design experiments approach. The introduction spirovinylethylene carbonates broadens scope these in catalytic applications provides an easy synthetic entry into scaffolds ring sizes.

Language: Английский

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Highly Chemoselective One‐Step Synthesis of Novel N‐Substituted‐Pyrrolo[3,4‐b]quinoline‐1,3‐diones via Palladium‐Catalyzed Aminocarbonylation/Carbonylative Cyclisation Sequence

European Journal of Organic Chemistry, Journal Year: 2023, Volume and Issue: 26(10)

Published: Feb. 13, 2023

Abstract Novel N ‐substituted pyrrolo[3,4‐b]quinoline‐1,3‐diones have been prepared via a highly chemoselective palladium‐catalyzed carbonylative imidazation‐cyclization reaction in one‐pot synthetic approach. This methodology, which has applied for the first time to access such original scaffolds through two different protocols involving 3‐bromo‐2‐iodoquinoline, as typical partner, primary amines, and atmospheric or high carbon monoxide pressure (20 bar), shown an excellent tolerance many functional groups. The use of bidentate ligands XantPhos dppp, either under high‐pressure conditions, provides wide range carbonylated compounds good yields (up 82 %). Furthermore, some new quinoline‐2,3‐dicarboxamides isolated side products very low fully characterized. solid state structures three synthesized acridinimides unequivocally established by single‐crystal XRD analysis.

Language: Английский

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Palladium-catalyzed stereoselective (3 + 2) cycloaddition of vinylethylene carbonates with cyclic N-sulfonyl ketimines

Organic & Biomolecular Chemistry, Journal Year: 2021, Volume and Issue: 19(22), P. 4877 - 4881

Published: Jan. 1, 2021

A diastereoselective (3 + 2) cycloaddition of N-sulfonyl ketimines with vinylethylene carbonates (VECs) in the presence Pd2dba3·CHCl3 and PPh3 has been developed. The reaction various substituted VECs diverse cyclic proceeded smoothly under mild conditions, giving highly functionalized oxazolidine frameworks good to excellent yields moderate diastereoselectivities. With use spiroketal-based diphosphine SKP as a chiral ligand, an asymmetric version current was achieved, products were obtained >99% ee most cases.

Language: Английский

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Dual Rh(II)/Pd(0) Relay Catalysis Involving Sigmatropic Rearrangement Using N-Sulfonyl Triazoles and 2-Hydroxymethylallyl Carbonates

Organic Letters, Journal Year: 2022, Volume and Issue: 24(38), P. 6951 - 6956

Published: Sept. 19, 2022

Dual Rh(II)/Pd(0) relay catalysis of N-sulfonyl triazoles and 2-hydroxymethylallyl carbonates has been developed, which affords pyrrolidines in moderate to good yields with high diastereoselectivities. The reaction proceeds via a mechanism involving O-H insertion onto the α-imino Rh(II)-carbene, [3,3]-sigmatropic rearrangement, dipole formation through Pd(0)-catalyzed decarboxylation, intramolecular N-allylation, leading multiple bonds one-pot operation.

Language: Английский

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Studies on the [4 + 2] cycloaddition and allylic substitution of indole-fused zwitterionic π-allylpalladium

Organic & Biomolecular Chemistry, Journal Year: 2023, Volume and Issue: 21(40), P. 8162 - 8169

Published: Jan. 1, 2023

The zwitterionic π-allylpalladium species, also known as dipoles, are important synthons widely used in various reactions including cycloaddition and allylic substitution. This study reported the development of a new indole-fused precursor compound its application [4 + 2] substitution reactions. As result, synthesis pyrrolo[3,2,1-ij]quinazolin-3-one 7-vinyl indole compounds was achieved with moderate to good yields. Notably, reaction exhibited excellent regio- stereoselectivity.

Language: Английский

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An organophotoredox-catalyzed C(sp²)–N cross coupling reaction of cyclic aldimines with cyclic aliphatic amines

Organic & Biomolecular Chemistry, Journal Year: 2021, Volume and Issue: 19(16), P. 3595 - 3600

Published: Jan. 1, 2021

An organophotocatalyzed C(sp2)-H/N-H cross-dehydrogenative coupling of cyclic aldimines with aliphatic amines has been developed, which represents the first example visible-light-induced C-H amination N-sulfonylated imines. This methodology enables streamline assembly amine derivatives via radical mediated C-N bond formation. The current protocol features transition-metal-free, mild conditions, good functional group tolerance and yields.

Language: Английский

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Catalytic Asymmetric Cycloadditions of Cyclic Sulfamidate Imines: Straightforward Access to Chiral N‐Heterocycles

Advanced Synthesis & Catalysis, Journal Year: 2024, Volume and Issue: 366(19), P. 3926 - 3942

Published: July 25, 2024

Abstract Chiral N‐heterocyclic compounds are key structures in natural and pharmaceuticals, they serve as essential building blocks of functional materials. Catalytic asymmetric cycloaddition reactions represent one the most efficient synthetic strategies for constructing optically active heterocycles. Cyclic sulfamidate imines have recently come to be extensively studied widely utilized both organocatalytic transition metal‐catalyzed cycloadditions, where been shown provide various N‐fused‐heterocycles spiro‐cycles exhibiting high efficiencies with excellent stereoselectivities. This review highlights recent advancements catalytic cycloadditions cyclic stereoselective synthesis biologically sulfamidate‐containing heterocycles since 2012 while focusing on diverse reactivities mechanisms chiral induction catalysis.

Language: Английский

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