(3+2) Annulation of Donor–Acceptor Cyclopropanes with Difluoroenoxysilanes: Syntheses of gem-Difluorocyclopentenes via α,α-Difluoroketone Scaffolds DOI
Neeraj Yadav, Prabal Banerjee

The Journal of Organic Chemistry, Год журнала: 2025, Номер unknown

Опубликована: Март 27, 2025

Herein, we present an acid- and base-mediated approach for ring opening of donor-acceptor cyclopropanes (DACs) followed by (3+2) annulation, yielding biologically relevant gem-difluorinated cyclopentenes via α,α-difluoroketone scaffolds. Fluorinated rings are essential building blocks in drug discovery materials research. This methodology has a broad substrate scope, is scalable, provides practical synthetic route to obtain value-added fluorinated compounds.

Язык: Английский

Intermediate Control: Unlocking Hitherto Unknown Reactivity and Selectivity in N-Conjugated Allenes and Alkynes DOI
Tapas R. Pradhan, Jin Kyoon Park

Accounts of Chemical Research, Год журнала: 2025, Номер 58(2), С. 281 - 298

Опубликована: Янв. 3, 2025

ConspectusControlling selectivity through manipulation of reaction intermediates remains one the most enduring challenges in organic chemistry, providing novel solutions for selective C-C π-bond functionalization. This approach, guided by activation principles, provides an effective method functional group installation, enabling direct synthesis molecules that are inaccessible conventional pathways. In particular, functionalization N-conjugated allenes and alkynes has emerged as a promising research focus, driven advances controlling reactive strategies. this regard, our group, alongside others, established some new approaches have suitable platform functionalized enamides. Account reviews recent developments field, highlighting modes reactivity selectivity, atom-economical functionalizations, strategies regio- stereocontrol, while mechanistic insights into related transformations.Our study is systematically organized two sections based on substrate type chronological progression. first section, we establish allenamide-derived intermediates, both allenamide-alkyne (AA) cross-coupling few electrophile-promoted hydrofunctionalization reactions. The unprecedented Pd-catalyzed achieved neighboring chelation, with phosphine ligand selection outcome. parallel, functionalizations─including haloalkynylation, hydrooxycarbonylation, hydrodifluoroalkylation, intermolecular hydroamination─are strategic electrophiles or their precursors.Additionally, findings demonstrate how ynamides' toward nucleophiles, controlled activator modulation, expands scope accessible transformations. Key include: (1) chemoselective [2 + 2 2] annulation efficient trapping N-arylated nitrilium ynamides, (2) divergent C-H indole-derived vinylogous ynamides metal via intramolecular hydroarylation, (3) bromoalkynylation-enabled migration 1,3-alkynyl shift.The final section explores N-electron polarization 1,3-enynes enables chemoselectivity metal-free inter- couplings indole substrates. Our modulating conjugation within enyne skeleton─through linear cross conjugation─can pathways control product selectivity.This aims to stimulate broader intermediate-controlled activated π-systems. Future directions include advanced design, strategies, deeper studies enable rational development.

Язык: Английский

Процитировано

2

Hydrogen-Bonding Network-Enabled Terminal Selective Heteroarylation of Allenamides in Hexafluoroisopropanol DOI
Sachin Balaso Mohite, Partha Sarathi Bera, Yafia Kousin Mirza

и другие.

Organic Letters, Год журнала: 2025, Номер unknown

Опубликована: Фев. 21, 2025

Hexafluoroisopropanol (HFIP)-mediated terminal selective heteroarylation of allenamides has been accomplished through H-bonding network-enabled substrate activation in a robust fashion. This strategy features cascade process involving sequential nucleophilic addition followed by electrophilic heteroaromatic substitution and is well suited for late-stage functionalization complex bioactive molecules. The elucidation the underlying mechanism was achieved comprehensive combination several control experiments, kinetic studies, isotopic labeling isolation HFIP-allenamide intermediate adduct.

Язык: Английский

Процитировано

1

(3+2) Annulation of Donor–Acceptor Cyclopropanes with Difluoroenoxysilanes: Syntheses of gem-Difluorocyclopentenes via α,α-Difluoroketone Scaffolds DOI
Neeraj Yadav, Prabal Banerjee

The Journal of Organic Chemistry, Год журнала: 2025, Номер unknown

Опубликована: Март 27, 2025

Herein, we present an acid- and base-mediated approach for ring opening of donor-acceptor cyclopropanes (DACs) followed by (3+2) annulation, yielding biologically relevant gem-difluorinated cyclopentenes via α,α-difluoroketone scaffolds. Fluorinated rings are essential building blocks in drug discovery materials research. This methodology has a broad substrate scope, is scalable, provides practical synthetic route to obtain value-added fluorinated compounds.

Язык: Английский

Процитировано

0