Formation of All-Carbon Quaternary Centers via Enantioselective Pd-Catalyzed α-Vinylation of γ-Lactams DOI Creative Commons
Farbod A. Moghadam, Jay P. Barbor, Melinda Chan

et al.

Organic Letters, Journal Year: 2024, Volume and Issue: 26(36), P. 7551 - 7554

Published: Sept. 3, 2024

Herein, we report an enantioselective vinylation of α-substituted γ-lactams that forges quaternary centers in up to 59% yield with 94% ee. The use canonically inactive vinyl chloride electrophiles afforded the highest yields and levels stereoselectivity, a range trisubstituted chlorides were found be proficient promoting this transformation. These stereogenic products could further elaborated functionally rich scaffolds, thereby highlighting synthetic utility process.

Language: Английский

Merging SOMO activation with transition metal catalysis: Deoxygenative functionalization of amides to β-aryl amines DOI Creative Commons

Tian Hongjun,

Feng Jiang,

Xiaoming Wang

et al.

Science Advances, Journal Year: 2025, Volume and Issue: 11(3)

Published: Jan. 17, 2025

Singly occupied molecular orbital (SOMO) activation of in situ generated enamines has achieved great success (asymmetric) α-functionalization carbonyl compounds. However, examples on the use this mode transformations other functional groups are rare, and combination SOMO with transition metal catalysis is still less explored. In area deoxygenative functionalization amides, intermediates such as iminium ions were often to result formation α-functionalized amines. contrast, direct deoxygenation amides β-functionalized amines highly appealing yet remains scarcely investigated. Here, a arylation aryl halides was developed via multicatalysis iridium/photoredox/nickel/iridium, affording β-aryl high efficiency. The key reaction enamine synergy Ni-catalyzed arylation, which conjunction two compatible Ir-catalyzed reduction processes.

Language: Английский

Citations

0
Bioinspired Copper/Amine Cooperative Catalysis Enables Asymmetric Radical Azidation DOI
Rui Wang, Yujie Liang,

Kang‐Jie Bian

et al.

Journal of the American Chemical Society, Journal Year: 2025, Volume and Issue: unknown

Published: Feb. 12, 2025

Asymmetric radical transformations (ARTs) are vital for constructing chiral drugs and materials, while the highly reactive nature of radicals often imposes a challenge in selectivity control these processes. Inspired by principles enzyme-cofactor cooperation to enhance stereochemical induction enantioselective transformations, we developed an asymmetric azidation via cooperative organo- transition metal catalysis. This approach enables efficient synthesis heavily functionalized tertiary azides from readily available aldehydes. The key this process is use both organocatalysts transiently convert aldehydes corresponding cationic species upon oxidation along with detailed screening metal-azide catalysts cooperatively stereoinduction carbon-azide bond formation. DFT studies suggest favorable stereocontrol model validate crucial roles chirality pairing catalytic schemes. We envision that copper/amine catalysis could offer useful strategy tetrasubstituted stereogenic carbon transformation development.

Language: Английский

Citations

0
Photoenolization of α,β-Unsaturated Esters Enables Enantioselective Contra-Thermodynamic Positional Isomerization to α-Tertiary β,γ-Alkenyl Esters DOI Creative Commons

Kuei-Chen Chang,

Hsien‐Yi Chiu,

Pin-Gong Huang

et al.

Journal of the American Chemical Society, Journal Year: 2025, Volume and Issue: 147(9), P. 7452 - 7460

Published: Feb. 24, 2025

The enantioselective protonation of prochiral enolates is an ideal and straightforward platform to synthesize stereodefined α-tertiary esters, which are recurring motifs in a myriad biorelevant molecules important intermediates thereof. However, this approach remains onerous, particularly when dealing with α-unactivated esters related acids, as enantioinduction on the nascent nucleophile necessitates peremptory reaction conditions, thus far only achieved via preformed enolates. A complementary contra-thermodynamic catalytic strategy herein described, where transient photoenol, form ketene hemiacetal, enantioselectively protonated chiral phosphoric acid (CPA). photoketene hemiacetals procured from excited α,β-unsaturated specifically Z-geometric isomer through [1,5]-hydride shift chemically productive nonradiative relaxation pathway. Tautomerization formal 1,3-proton transfer hemiacetal CPA proton shuttle delivers α-branched β,γ-alkenyl good excellent yields enantioselectivity under mild conditions. Furthermore, current protocol was coupled functional group interconversion experiments, well total synthesis known marine γ-butyrolactone-type metabolite. Performing continuous photoflow setup also enabled gram-scale ester up 92% ee.

Language: Английский

Citations

0
Harnessing visible light for alkenylation reactions: A promising strategy in organic synthesis DOI

M. Manod,

Archana Vijayakumar,

TS Abhinav

et al.

Molecular Catalysis, Journal Year: 2025, Volume and Issue: 579, P. 115028 - 115028

Published: March 22, 2025

Language: Английский

Citations

0
Formation of All-Carbon Quaternary Centers via Enantioselective Pd-Catalyzed α-Vinylation of γ-Lactams DOI Creative Commons
Farbod A. Moghadam, Jay P. Barbor, Melinda Chan

et al.

Organic Letters, Journal Year: 2024, Volume and Issue: 26(36), P. 7551 - 7554

Published: Sept. 3, 2024

Herein, we report an enantioselective vinylation of α-substituted γ-lactams that forges quaternary centers in up to 59% yield with 94% ee. The use canonically inactive vinyl chloride electrophiles afforded the highest yields and levels stereoselectivity, a range trisubstituted chlorides were found be proficient promoting this transformation. These stereogenic products could further elaborated functionally rich scaffolds, thereby highlighting synthetic utility process.

Language: Английский

Citations

3