Direct access to spirooxindole dihydropyrrole fused pyrazolones and bis-spiropyrazolone derivatives

Warghude, Prakash K.; Bhowmick, Anindita; Bhat, Ramakrishna G.

doi:10.1016/j.tetlet.2022.153791

Cited by 7 publications

(4 citation statements)

References 61 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…On the basis of our experimental results and previous reports in the literature, 17 , 19b d , 20 22 26 a plausible catalytic cycle for [3+2] cycloaddition reaction is proposed (Scheme 5 ). Nucleophilic attack by DMAP on the pyrazolone-derived MBH carbonate 1a generates the corresponding quaternary ammonium salt A together with a tert -butoxide anion and carbon dioxide.…”

Section: Table 1 Optimization Of the Reaction Condition...supporting

confidence: 68%

See 1 more Smart Citation

An Efficient Route to Access Spirooxindole–Pyrazolone-Fused Cyclopentenes by a Diastereoselective [3+2] Annulation

Sabale¹,

Warghude²,

Bhat³

2023

Synlett

Self Cite

View full text Add to dashboard Cite

A DMAP catalyzed highly diastereoselective [3 + 2] cycloaddition of pyrazolone derived Morita-Baylis-Hillman (MBH) carbonate and 3-methyleneoxindole has been developed. A variety of structurally diverse and complex spiropyrazolone fused oxindoles bearing three contiguous chiral centers have been synthesized in very high yields (up to 98%) with excellent diastereoselectivity (up to 99:1). Moreover, the synthetic potential of this protocol has been demonstrated by performing Suzuki coupling reaction.

show abstract

Section: Table 1 Optimization Of the Reaction Condition...supporting

confidence: 68%

“…As part of our continuing interest in the synthesis of spirocyclic compound and our ongoing research on cycloaddition reactions of isatin-based Morita–Baylis–Hillman (MBH) carbonates, 19a b 20 we became interested in the synthesis of spirooxindole-fused pyrazolone molecules.…”

Section: Table 1 Optimization Of the Reaction Condition...mentioning

confidence: 99%

An Efficient Route to Access Spirooxindole–Pyrazolone-Fused Cyclopentenes by a Diastereoselective [3+2] Annulation

Sabale¹,

Warghude²,

Bhat³

2023

Synlett

Self Cite

View full text Add to dashboard Cite

show abstract

“…Recnetly, Bhat and coworkers developed a DMAP‐catalyzed [3+2] cycloaddition of Morita–Baylis–Hillman carbonates of isatins with pyrazolone derived ketimines [20] . As shown in Scheme 11, the protocol worked effectively to construct spirooxindole dihydropyrrole fused pyrazolones in good to excellent yields with very high diastereoselectivity (Scheme 11).…”

Section: Tertiary Amine‐catalyzed Cyclo‐additions For the Constructio...mentioning

confidence: 99%

Recent Advances in Nucleophilic Lewis Base‐Catalyzed Cycloadditions for Synthesis of Spirooxindoles

Li,

Ma,

Meng

et al. 2023

Adv Synth Catal

View full text Add to dashboard Cite

Spirooxindoles are privileged scaffolds in diverse bioactive natural products and pharmaceuticals, significant achievements for the construction of these molecules have thus been made in the past years. Among them, organocatalysis, in particular, nucleophilic Lewis base catalysis, has recently emerged as an efficient and reliable method for the preparation of diverse and valuable functionalized spirooxindoles. According to different kinds of nucleophilic catalysts, we summarize and classify three catalytic strategies; these are tertiary amine‐catalyzed cycloadditions, NHC‐catalyzed cycloadditions, and tertiary phosphine‐catalyzed cycloadditions, respectively. Through these methods, potential bioactive spirooxindole skeletons owning various functional groups can be produced to enrich the small organic molecule library. In this review, we describe a comprehensive and updated advances of nucleophilic Lewis base catalytic cycloaddition reactions for the construction of spirooxindoles. Meanwhile, the related mechanism and the application of these annulation strategies in natural product total synthesis will be highlighted in detail.

show abstract

“…在 2018～2019 年, Ge [7] , Liu [8] 、 Du [9] 和 Yan [10] 等课题组先后在该领域取得重要的突破. 此外, Bhat 等分别于 2020 年 [11] 和 2022 年 [12] 利用有机小分子催化剂参与 Morita-Baylis-Hillman [3＋2]环化反应, 成功构建了螺环氧化吲哚稠合吡唑啉酮化合物(Scheme 1, c). 综上所述, 尽管一些合成化学家已经利用有机小分子催化成功合成了含有吡唑啉酮结构的螺环氧化吲哚化合物, 但目前的研究报道依然比较有限.…”

unclassified

N-Heterocyclic Carbene (NHC)-Catalyzed [3+2] Cycloaddition to Highly Diastereoselective Synthesis of Spirooxindole Dihydrofuran Fused Pyrazolone Compounds

Liu,

Wang,

et al. 2024

Chinese Journal of Organic Chemistry

View full text Add to dashboard Cite

An efficient N-heterocyclic carbene (NHC)-catalyzed [3＋2] cycloaddition of isatin-derived enal and pyrazole-4,5diones to directly synthesis of spirooxindole dihydrofuran fused pyrazolone compounds containing two vicinal spirocenters was disclosed. This approach was qualified with broad substrate scope, achieving moderate to excellent yield (41%～99%) and general to excellent diastereoselective (2∶1～＞20∶1 dr). Furthermore, the reaction has the advantages of mild reaction conditions and easy operation, and the gram scale reaction can also proceed smoothly. This study provides a new synthetic methodology for the efficient construction of multi-functionalized spirooxindole dihydrofuran fused pyrazolone compounds.

show abstract

Direct access to spirooxindole dihydropyrrole fused pyrazolones and bis-spiropyrazolone derivatives

Cited by 7 publications

References 61 publications

An Efficient Route to Access Spirooxindole–Pyrazolone-Fused Cyclopentenes by a Diastereoselective [3+2] Annulation

An Efficient Route to Access Spirooxindole–Pyrazolone-Fused Cyclopentenes by a Diastereoselective [3+2] Annulation

Recent Advances in Nucleophilic Lewis Base‐Catalyzed Cycloadditions for Synthesis of Spirooxindoles

N-Heterocyclic Carbene (NHC)-Catalyzed [3+2] Cycloaddition to Highly Diastereoselective Synthesis of Spirooxindole Dihydrofuran Fused Pyrazolone Compounds

Contact Info

Product

Resources

About