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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Palladium-catalyzed and ligand-controlled divergent cycloadditions of vinylidenecyclopropane-diesters with para-quinone methides enabled by zwitterionic π-propargyl palladium species

Organic Chemistry Frontiers, Journal Year: 2024, Volume and Issue: 11(11), P. 3214 - 3224

Published: Jan. 1, 2024

A palladium-catalyzed and ligand-controlled divergent synthesis of spiro-cyclohexadienones from p -quinone methides VDCP-diesters was realized via zwitterionic π-propargyl palladium species the mechanism clarified by DFT calculations.

Language: 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, Journal Year: 2024, Volume and Issue: 27(25)

Published: April 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.

Language: Английский

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Palladium-Catalyzed Cycloaddition Reactions of π–Allylpalladium 1,4-Dipoles with 1,3,5-Triazinanes: Access to Hexahydropyrimidines, 1,3-Oxazinanes, and 1,5-Diazocanes

The Journal of Organic Chemistry, Journal Year: 2024, Volume and Issue: 89(12), P. 8363 - 8375

Published: June 7, 2024

Palladium-catalyzed decarboxylation of 5-methylene-1,3-oxazinan-2-ones and 5-methylene-1,3-dioxan-2-ones to generate aza-π-allylpalladium oxa-π-allylpalladium 1,4-dipoles for [4 + 2] cycloaddition reaction with 1,3,5-triazinanes was developed, affording a wide range hexahydropyrimidine 1,3-oxazinane derivatives in good excellent yields (up 99%). The acyclic sulfonamido-substituted allylic carbonates as 1,4-dipole precursors also apply the developed synthesized strategy, achieving synthesis hexahydropyrimidines. Moreover, situ-generated undergoing dimeric 4] were demonstrated by construction 1,5-diazocane derivatives.

Language: Английский

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

The Journal of Organic Chemistry, Journal Year: 2024, Volume and Issue: 89(15), P. 10551 - 10556

Published: July 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.

Language: Английский

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