Enantioselective [2π + 2σ] cycloaddition of bicyclobutanes with imines: An efficient approach to chiral 2-aza-bicyclo[2.1.1]hexanes

Chem Catalysis, Год журнала: 2025, Номер unknown, С. 101295 - 101295

Опубликована: Март 1, 2025

Язык: Английский

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Borylated strain rings synthesis via photorearrangements enabled by energy transfer catalysis

Nature Communications, Год журнала: 2025, Номер 16(1)

Опубликована: Апрель 19, 2025

Язык: Английский

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Catalytic Intermolecular Asymmetric [2π + 2σ] Cycloadditions of Bicyclo[1.1.0]butanes: Practical Synthesis of Enantioenriched Highly Substituted Bicyclo[2.1.1]hexanes

Journal of the American Chemical Society, Год журнала: 2024, Номер unknown

Опубликована: Дек. 3, 2024

The high percentage of sp

Язык: Английский

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Zwitterionic π-Allyl-Pd Species Enabled [2σ+2π] Cycloaddition Reactions of Vinylbicyclo[1.1.0]butanes (VBCBs) with Alkenes, Carbonyls, and Imines

ACS Catalysis, Год журнала: 2024, Номер 14(24), С. 18799 - 18809

Опубликована: Дек. 11, 2024

Transition-metal-catalyzed cycloaddition reactions of strained small-ring compounds are powerful methods for constructing carbo- and heterocyclic structures medicinal interest. However, the application this strategy to bicyclo[1.1.0]butanes (BCBs), which among most carbocycles known, remains underdeveloped. Herein, we report vinylbicyclo[1.1.0]butane (VBCB) as a platform synthon palladium-catalyzed formal [2σ+2π] with various 2π-components, enabling synthesis BCHs, oxa-BCHs, aza-BCHs under identical reaction conditions. The zwitterionic π-allyl-Pd species generated through activation VBCBs is key circumventing potential carbene reactivity serves common intermediate cycloadditions diverse 2π-systems, including alkenes, aldehydes, ketones, imines. Notably, by utilizing Pd2(dba)3 an anthracene-derived Trost ligand, wide array BCHs bearing two vicinal chiral centers has been prepared in highly diastereo-, enantioselective manner. generality practicality method have demonstrated broad substrate scope, scale-up reactions, versatile transformation multiple functional groups into BCH scaffolds. Preliminary mechanistic studies support formation species.

Язык: Английский

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Divergent Synthesis of Sulfur‐Containing Bridged Cyclobutanes by Lewis Acid Catalyzed Formal Cycloadditions of Pyridinium 1,4‐Zwitterionic Thiolates and Bicyclobutanes

Angewandte Chemie, Год журнала: 2024, Номер 136(40)

Опубликована: Май 31, 2024

Abstract Bridged cyclobutanes and sulfur heterocycles are currently under intense investigation as building blocks for pharmaceutical drug design. Two formal cycloaddition modes involving bicyclobutanes (BCBs) pyridinium 1,4‐zwitterionic thiolate derivatives were described to rapidly expand the chemical space of sulfur‐containing bridged cyclobutanes. By using Ni(ClO 4 ) 2 catalyst, an uncommon higher‐order (5+3) BCBs with quinolinium was achieved broad substrate scope mild reaction conditions. Furthermore, first Lewis acid‐catalyzed asymmetric polar BCB pyridazinium accomplished. In contrast, thiolates undergo Sc(OTf) 3 ‐catalyzed (3+3) generate thia‐norpinene products, which represent initial instance synthesizing 2‐thiabicyclo[3.1.1]heptanes (thia‐BCHeps) from BCBs. Moreover, we have successfully used this protocol prepare thia‐BCHeps‐substituted analogues bioactive molecule Pitofenone. Density functional theory (DFT) computations imply that kinetic factors govern between thiolate, whereas is thermodynamic control.

Язык: Английский

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A general synthesis of gem-difluorobicyclo[2.1.1]hexanes

Chinese Chemical Letters, Год журнала: 2024, Номер unknown, С. 110213 - 110213

Опубликована: Авг. 1, 2024

Язык: Английский

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PolyBorylated Alkenes as Energy‐Transfer Reactive Groups: Access to Multi‐Borylated Cyclobutanes Combined with Hydrogen Atom Transfer Event

Angewandte Chemie, Год журнала: 2024, Номер 136(25)

Опубликована: Апрель 11, 2024

Abstract While polyborylated alkenes are being recognized for their elevated status as highly valuable reagents in modern organic synthesis, allowing efficient access to a diverse array of transformations, including the formation C−C and C‐heteroatom bonds, potential energy‐transfer reactive groups has remained unexplored. Yet, this holds key generating elusive biradical species, which can be captured by olefins, thereby leading construction new highly‐borylated scaffolds. Herein, we report designed strategy photosensitized [2+2]‐cycloadditions poly‐borylated with various olefins enabling regioselective synthesis cyclobutane motifs, 1,1‐di‐, 1,1,2‐tri‐, 1,1,2,2‐tetra‐borylated cyclobutanes. In fact, these compounds belong family that presently lacks synthetic pathways. Interestingly, when α‐methylstyrene was used, reaction involves an interesting 1,5‐hydrogen atom transfer (HAT). Mechanistic deuterium‐labeling studies have provided insight into outcome process. addition, cyclobutanes then demonstrated useful selective oxidation processes resulting cyclobutanones γ‐lactones.

Язык: Английский

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Regioselectivity of non-Symmetrical Borylated Dienes via EnT Ca-talysis: Unveiling the Relationship between Structure and Reactivity

Опубликована: Авг. 16, 2024

Energy transfer catalysis (EnT) has had a profound impact on contemporary organic synthesis enabling the construction of higher in energy, complex molecules, via efficient access to triplet excited state. Despite this, intermolecular reactivity, and unique possibility several reaction pathways central diradical rendered control over outcomes, an intractable challenge. Extended chromophores such as non-symmetrical dienes have potential undergo 2+2 cycloaddition, 4+2 cycloaddition or geometric isomerization, which, combination with other mechanistic considerations (site- regioselectivity), results chemical reactions that are challenging regulate. Leveraging spin density predictive tool, use core functionality can be adequately tuned potentially modulate would highly revealing intimate links between structure EnT induced reactivity. Herein, we utilize boron tool explore reactivity under catalysis, paying particular attention hybridization effects target Through site- regioselective was realized employed motif effecting efficiency. Reaction divergence enable achieved, while counterintuitive regiodivergence observed isomerization versus cycloaddition. The validated in-depth investigation determining origin competing processes

Язык: Английский

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Three-component cascade carbopalladation/Heck cyclization/borylation: facile access to boryl-functionalized indenes

Chemical Communications, Год журнала: 2024, Номер 60(62), С. 8075 - 8078

Опубликована: Янв. 1, 2024

A mild Pd-catalyzed three-component cascade cyclization functionalization of

Язык: Английский

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[2 + 2] Photocycloadditions to Form Cyclobutanes and Bicyclo[2.1.1]hexanes Employing Copper-Based Photocatalysis

ACS Catalysis, Год журнала: 2024, Номер 14(15), С. 11490 - 11497

Опубликована: Июль 18, 2024

Язык: Английский

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