Pd-Catalyzed Ligand-Directed Divergent Cycloaddition of Cyclic 1-Azadienes with Oxo-1,4-dipoles

Organic Letters, Год журнала: 2023, Номер 25(27), С. 5011 - 5016

Опубликована: Июнь 29, 2023

Ligand-directed divergent synthesis (LDS) is an important synthetic tool for the preparation of structurally diverse organic molecules without tedious steps to modify substrates. Herein, we introduce realization 3,4-, 1,2-, and 1,4-cyclization benzo[d]isothiazole-1,1-dioxide-fused azadienes (BDAs) through LDS, leading tetrahydro-2H-pyrans, oxazinanes, tetrahydro-2H-1,5-oxazocines, respectively. Using phosphinooxazoline (PHOX) ligands, have developed a [4 + 2] cycloaddition between BDAs substituted 2-alkylidenetrimethylene carbonates, providing access multi-substituted chiral tetrahydro-2H-pyrans in good yields with excellent enantio-, diastereo-, regioselectivities.

Язык: Английский

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Copper-Catalyzed Enantioselective Formal [4 + 1] and [3 + 3] Cycloaddition of Ethynylethylene Carbonates

Organic Letters, Год журнала: 2023, Номер 25(51), С. 9213 - 9218

Опубликована: Дек. 15, 2023

Herein we employed ethynylethylene carbonates (EECs) to achieve formal [4 + 1] and [3 3] cycloaddition with cyclic 1,3-dicarbonyl compounds. On one hand, EECs styryl substitution could undergo a remotely controlled enantioselective reaction. This reaction exhibits good chemoselectivity, regioselectivity, enantioselectivity. In addition, of compounds was also achieved, leading series 4H-pyrans impressive chemoselectivity

Язык: Английский

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Tandem Allylic Amination/oxa-Michael Addition of Vinyl Methylene Cyclic Carbonates via Palladium-Organo Relay Catalysis

Organic Letters, Год журнала: 2023, Номер 25(30), С. 5624 - 5629

Опубликована: Июль 24, 2023

A tandem allylic amination/oxa-Michael addition of vinyl methylene cyclic carbonates (VMCCs) has been developed to construct heterocycles by single palladium catalysis or palladium-organo relay catalysis. In this process, the bisnucleophiles first underwent regioselective amination, and then second nucleophilic group further completed hetero-Michael reaction form a series heterocycles. Among them, chiral 3,4-dihydro-2H-benzo[b][1,4]oxazines could be produced in medium high yield with good enantioselectivity under

Язык: 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, Год журнала: 2023, Номер 42(8), С. 829 - 834

Опубликована: Дек. 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.

Язык: Английский

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Synthesis of medium-sized heterocycles from oxetanes based on an allylic amination/ring-opening strategy

Chemical Communications, Год журнала: 2023, Номер 59(97), С. 14467 - 14470

Опубликована: Янв. 1, 2023

The construction of medium-sized ring compounds has been a prominent research area in synthetic chemistry. In this study, we developed tandem strategy that combines allylic amination and ring-opening oxetanes to synthesize heterocycles. Specifically, N-aryl oxetan-3-amines undergo with zwitterionic π-allylpalladium, followed by intramolecular ring-opening, resulting the formation Notably, are able achieve synthesis 7-8 membered heterocycles moderate good yields employing different types π-allylpalladium species.

Язык: Английский

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Asymmetric 2,4-Dienylation/[4 + 2] Annulation Cascade to Construct Fused Frameworks via Auto-Tandem Palladium Catalysis

Organic Letters, Год журнала: 2023, Номер 25(20), С. 3682 - 3686

Опубликована: Май 16, 2023

A palladium catalyzed tandem reaction between ortho-functionalized aryl enones and 2,4-dienyl carbonates has been presented, proceeding through sequential 2,4-dienylation/Michael addition/π-σ-π isomerization/allylic alkylation. broad array of enantioenriched architectures having fused spirocyclic frameworks are constructed in moderate to excellent yields stereoselectivity. Notably, the intrinsic intramolecular Diels-Alder pattern dienylated intermediates is well reversed via Pd(0)-π-Lewis base catalysis.

Язык: Английский

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Rapid Access to Divergent Fused Polycycles Via One‐Pot A³ Coupling and Intramolecular Diels‐Alder Reaction

Chemistry - A European Journal, Год журнала: 2024, Номер 30(41)

Опубликована: Май 16, 2024

Abstract Divergent nitrogen‐containing fused polycyclic ring systems are constructed from simple starting materials via a one‐pot aldehyde‐alkyne‐amine (A 3 ) coupling and intramolecular Diels‐Alder reaction. This domino reaction directly furnishes linear 5/5/5 5/5/6, or nonlinear 5/5/6/5, rings containing an oxa‐bridged 5/5 bicycle 1,6‐enyne substructure. One‐step derivation of the leads to polyfunctionalized with tetrahydrofuran back‐to‐back pyrroline 6/5 hexahydro‐1 H ‐isoindole structure, while cycloisomerizing enyne substructure adds extra 5‐membered afford functionalized 5/5/5/5 5/5/5/5/5 selected substrates. In addition, product can be designed so that alkyne moiety is hydroalkoxylated form additional heterocyle in 5/5/5/6 5/5/6/5/5 system. diversity‐oriented synthetic approach thus allows rapid access under‐explored structural space for discovery new biological non‐biological activities functions.

Язык: Английский

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

Organic & Biomolecular Chemistry, Год журнала: 2023, Номер 21(40), С. 8162 - 8169

Опубликована: Янв. 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.

Язык: Английский

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Copper‐Catalyzed Formal [4+2] Cycloaddition of Ethynylethylene Carbonates for the Construction of 3,4‐Dihydro‐2H‐benzo[b][1,4]oxazines

European Journal of Organic Chemistry, Год журнала: 2024, Номер 27(25)

Опубликована: Апрель 9, 2024

Abstract A formal [4+2] cycloaddition reaction of ethynylethylene carbonates and 2‐aminophenols has been developed for the synthesis 3,4‐dihydro‐2 H ‐benzo[ b ][1,4]oxazines bearing quaternary carbon atoms. The features mild conditions, good functional group compatibility yields. Furthermore, when using chiral PyBox ligand, this strategy could also achieve asymmetric ][1,4]oxazines. Application studies indicated that hydroxymethyl final products was an excellent can be further modified easily.

Язык: Английский

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Type of Tetrahydronaphthalene-Fused 1,5-Dipoles and Their Application in Polycyclic Compounds Synthesis

The Journal of Organic Chemistry, Год журнала: 2024, Номер 89(15), С. 10551 - 10556

Опубликована: Июль 17, 2024

Palladium-catalyzed dipolar cycloaddition reactions represent an efficient strategy for the construction of cyclic compounds, with development novel precursors being a key focus. In this study, new type precursor was synthesized through assembly vinylethylene carbonate unit and tetrahydronaphthalene skeleton. This can undergo [3 + 2], [5 4], 2] reactions, leading to tetrahydronaphthalene-fused oxazolidin-2-ones, 1,5-oxazonines, tetrahydrooxepines. general, all these exhibited good reaction efficiency functional group tolerance.

Язык: Английский

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