Synthesis of tetrahydrochromenes and dihydronaphthofurans via a cascade process of [3 + 3] and [3 + 2] annulation reactions: mechanistic insight for 6-endo-trig and 5-exo-trig cyclisation

RSC Advances, Год журнала: 2023, Номер 13(9), С. 5796 - 5803

Опубликована: Янв. 1, 2023

Substituted tetrahydrochromenes and dihydronaphthofurans are easily accessible by the treatment of β-tetralone with trans-β-nitro styrene derived Morita-Baylis-Hillman (MBH) acetates through a formal [3 + 3]/[3 2] annulation. The reaction proceeds cascade Michael/oxa-Michael pathway moderate to good yields. A DFT study was carried out account for formation corresponding six five-membered heterocycles via 6-endo-trig 5-exo-trig cyclization.

Язык: Английский

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Solvent Directed Diastereodivergent Synthesis of Spiro‐Oxindoles with Quaternary Carbon Center Forming

European Journal of Organic Chemistry, Год журнала: 2023, Номер 26(38)

Опубликована: Авг. 12, 2023

Abstract An efficient method has been developed for the solvent‐directed diastereodivergent cyclization reactions with quaternary center formation. Various spiro‐oxindole diastereoisomers were synthesized good yields (up to >99 %) and moderate high diastereoselectivities >20 : 1). Further study on NMR studies indicates that key this approach lies in different interactions between substrate organocatalyst across diverse solvents. This methodology may have significant implications switchable, synthesis.

Язык: Английский

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Access to densely functionalized spirocyclopentenonyl oxindole frameworks via aza- and carbo-Piancatelli rearrangement

Organic & Biomolecular Chemistry, Год журнала: 2022, Номер 20(26), С. 5249 - 5253

Опубликована: Янв. 1, 2022

The Piancatelli rearrangement on an oxindole-based template enables access to highly functionalized spirooxindole moieties.

Язык: Английский

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Synthesis of 2,3-bifunctional imidazo[1,2-a]pyridines through cycloadditions of pyridinium ylides with N-cyano-4-methyl-N-phenylbenzenesulfonamide

Tetrahedron Letters, Год журнала: 2022, Номер 115, С. 154295 - 154295

Опубликована: Дек. 6, 2022

Язык: Английский

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Asymmetric organocatalytic Morita−Baylis−Hillman reaction and asymmetric organocatalytic transformations of Morita−Baylis−Hillman adducts. An update

Tetrahedron, Год журнала: 2024, Номер 172, С. 134435 - 134435

Опубликована: Дек. 23, 2024

Язык: Английский

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Asymmetric Synthesis of Tricycle‐Fused Dispirooxindoles via Organocatalyzed Three‐Component Cascade Reactions of 2‐Pyrones and Trifluoroethylisatin Ketimines

Advanced Synthesis & Catalysis, Год журнала: 2022, Номер 364(22), С. 3888 - 3894

Опубликована: Окт. 7, 2022

Abstract An asymmetric synthesis of a series tricycle‐fused dispirooxindoles frameworks assembled in different rings was disclosed via multicomponent cascade 1,3‐dipolar cycloadditions electron‐deficient 2‐pyrones and trifluoroethylisatin ketimines under the catalysis hydroquinine or (DHQD) 2 PHAL with 61→99% ee >19:1 dr. Meanwhile, these potentially biologically important fused pyrrolidinyl/tetrahydropyranone/pyrrolidinyl frame‐works bear eight contiguous stereocenters functionalized pharmacophores which could further transfer to linaer spirooxindoles bearing epoxyethyl moiety retentive enantioselectivity. magnified image

Язык: Английский

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Multicomponent reaction (MCR) for constructing bis-spirocyclohexane skeletons using β-nitrostyrene derived MBH acetates, 1,3-indanedione and aldehydes via [1 + 1 + 1 + 3] annulation

RSC Advances, Год журнала: 2023, Номер 13(39), С. 27456 - 27460

Опубликована: Янв. 1, 2023

AB 2 C type four component quadruple cascade reaction between MBH acetate, 1,3-indanedione and aldehydes via [1 + 1 3] annulation progressed through Knoevenagel/Michael/Michael/Michael sequence for the synthesis of b is-spirocyclohexane.

Язык: Английский

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Miscellaneous (3 + 2) Cycloadditions

Elsevier eBooks, Год журнала: 2022, Номер unknown, С. 215 - 246

Опубликована: Дек. 13, 2022

Язык: Английский

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