Visible Light Organo‐Photocatalytic Synthesis of 3‐Imidazolines DOI

Poornima Mishra,

Ipsha Shruti,

Ruchir Kant

et al.

European Journal of Organic Chemistry, Journal Year: 2022, Volume and Issue: 2022(44)

Published: Nov. 25, 2022

Abstract An efficient regioselective synthesis of tetrasubstituted 3‐imidazolines under organo‐photocatalytic conditions has been developed through formal [3+2]‐cycloaddition between 2 H ‐azirines and N ‐tosyl benzylidene imines. The products were isolated in high yields as a separable mixture diastereoisomers most the cases. mild reaction employing an organic dye photocatalyst, excellent functional group tolerance, regioselectivity are notable features current protocol.

Language: Английский

(Z)-Selective Isomerization of 1,1-Disubstituted Alkenes by Scandium-Catalyzed Allylic C–H Activation DOI
Shao‐Jie Lou, Pan Wang, Xin Wen

et al.

Journal of the American Chemical Society, Journal Year: 2024, Volume and Issue: 146(39), P. 26766 - 26776

Published: Sept. 20, 2024

The isomerization of 1,1-disubstituted alkenes through 1,3-hydrogen shift is an atom-efficient route for synthesizing trisubstituted alkenes, which are important moieties in many natural products, pharmaceuticals, and organic materials. However, this reaction often encounters regio- stereoselectivity challenges, typically yielding

Language: Английский

Citations

8
Alkene Isomerization Using a Heterogeneous Nickel-Hydride Catalyst DOI

Alison Sy-min Chang,

Melanie A. Kascoutas,

Quinn Valentine

et al.

Journal of the American Chemical Society, Journal Year: 2024, Volume and Issue: 146(22), P. 15596 - 15608

Published: May 21, 2024

Transition metal-catalyzed alkene isomerization is an enabling technology used to install distal its original site. Due their well-defined structure, homogeneous catalysts can be fine-tuned optimize reactivity, stereoselectivity, and positional selectivity, but they often suffer from instability nonrecyclability. Heterogeneous are generally highly robust continue lack active-site specificity challenging rationally improve through structural modification. Known single-site heterogeneous for utilize precious metals bespoke, expensive, synthetically intense supports. Additionally, have mediocre inspiring us develop a catalyst with active site made readily available compounds of Earth-abundant elements. Previous work demonstrated that very formed upon protonation Ni[P(OEt)3]4 by H2SO4, generating [Ni–H]+ This incredibly active, also decomposes readily, which severely limits utility. Herein we show using solid acid (sulfated zirconia, SZO300), not only this decomposition prevented, high activity maintained, improved selectivity achieved, broader scope functional groups tolerated. Preliminary mechanistic experiments suggest the catalytic reaction likely goes intermolecular, two-electron pathway. A detailed kinetic study comparing state-of-the-art Ni Pd reveals highest seen Ni/SZO300 system. The reactivity Ni/SZO300, limited isomerization; it competent hydroalkenylation, hydroboration, hydrosilylation, demonstrating broad application catalyst.

Language: Английский

Citations

7
Highly Regioselective Cobalt‐Catalyzed Hydroboration of Internal Alkynes DOI

Yan‐Dong Zhang,

Xiao‐Yu Li,

Qian‐Kun Mo

et al.

Angewandte Chemie International Edition, Journal Year: 2022, Volume and Issue: 61(36)

Published: July 13, 2022

Herein, we report the development of new Co complexes that have cyclopropane-based diphosphine ligands and can catalyze highly chemo-, regio-, stereoselective hydroboration reactions unsymmetrical internal alkynes. These exhibited unusual regioselectivity: specifically, aryl alkyl alkynes showed excellent cis-β-addition selectivity, dialkyl gave cis-α-addition selectivity. Highly regioselective cannot be achieved by other known methods. The described herein are synthetically useful, particularly for synthesis trisubstituted alkenylborates alkenes. Mechanistic studies indicate a CoI -H species is plausible active catalyst rigid structure cyclopropane skeleton crowded reaction pocket were responsible unprecedented regioselectivity.

Language: Английский

Citations

29
Trisubstituted alkenes featuring aryl groups: stereoselective synthetic strategies and applications DOI Open Access
Mengyao Li,

Shuyang Zhai,

Xiao‐Mei Nong

et al.

Science China Chemistry, Journal Year: 2023, Volume and Issue: 66(5), P. 1261 - 1287

Published: April 17, 2023

Language: Английский

Citations

14
Switching between Hydrogenation and Olefin Transposition Catalysis via Silencing NH Cooperativity in Mn(I) Pincer Complexes DOI Creative Commons
Wenjun Yang, Ivan Yu. Chernyshov, Manuela Weber

et al.

ACS Catalysis, Journal Year: 2022, Volume and Issue: 12(17), P. 10818 - 10825

Published: Aug. 19, 2022

While Mn-catalyzed (de)hydrogenation of carbonyl derivatives has been well established, the reactivity Mn hydrides with olefins remains very rare. Herein, we report a Mn(I) pincer complex that effectively promotes site-controlled transposition olefins. This is shown to emerge once N-H functionality within Mn/NH bifunctional suppressed by alkylation. detrimental for (de)hydrogenation, such masking cooperative allows highly efficient conversion wide range allylarenes higher-value 1-propenybenzenes in near-quantitative yield excellent stereoselectivities. The toward single positional isomerization was also retained long-chain alkenes, resulting regioselective formation 2-alkenes, which are less thermodynamically stable compared other possible products. detailed mechanistic analysis reaction between activated catalyst and points catalysis operating via metal-alkyl mechanism-one three conventional mechanisms previously unknown complexes.

Language: Английский

Citations

23
Synthesis of Tri‐ and Tetrasubstituted Alkenyl Boronates from Alkynes DOI Creative Commons
Julia Altarejos, Antonio Valero-Martínez, Rubén Manzano

et al.

European Journal of Organic Chemistry, Journal Year: 2022, Volume and Issue: 2022(30)

Published: July 8, 2022

Abstract The synthesis of organoboron compounds have attracted the attention synthetic community. In particular, molecules with C(sp 2 )‐B bonds enable transformation to new C−C or C‐heteroatom by well‐established methodologies. Alkenyl boronates possibility for further conversion boron moiety functionalization double bond. This review gives an overview on recent methodologies selective preparation challenging highly substituted alkenyl from alkynes.

Language: Английский

Citations

22
Iron‐Catalyzed Positional and Geometrical Isomerization of Alkenes DOI Creative Commons
A. Obeid, Jérôme Hannedouche

Advanced Synthesis & Catalysis, Journal Year: 2023, Volume and Issue: 365(8), P. 1100 - 1111

Published: Feb. 20, 2023

Abstract This review outlines the most noteworthy achievements of last few years in renascent field positional and geometrical isomerization alkenes using iron catalysis, from a mechanistic perspective. Particular attention will be placed on developments beyond seminal contributions carbonyl complexes their aspects underlying nature active species. The relevant literature has been covered until late 2022. magnified image

Language: Английский

Citations

12
Ligand-enabled stereodivergence in nickel-catalyzed regioselective hydroboration of internal allenes DOI Creative Commons
Xiaoxu Yang, Chunchen Yuan, Shaozhong Ge

et al.

Chem, Journal Year: 2022, Volume and Issue: 9(1), P. 198 - 215

Published: Nov. 2, 2022

Language: Английский

Citations

18
DMDA-PatA mediates RNA sequence-selective translation repression by anchoring eIF4A and DDX3 to GNG motifs DOI Creative Commons
Hironori Saito, Yuma Handa, Mingming Chen

et al.

Nature Communications, Journal Year: 2024, Volume and Issue: 15(1)

Published: Sept. 2, 2024

Small-molecule compounds that elicit mRNA-selective translation repression have attracted interest due to their potential for expansion of druggable space. However, only a limited number examples been reported date. Here, we show desmethyl desamino pateamine A (DMDA-PatA) represses in an manner by clamping eIF4A, DEAD-box RNA-binding protein, onto GNG motifs. By systematically comparing multiple eIF4A inhibitors ribosome profiling, found DMDA-PatA has unique mRNA selectivity repression. Unbiased Bind-n-Seq reveals DMDA-PatA-targeted exhibits preference motifs ATP-independent manner. This unusual RNA binding sterically hinders scanning 40S ribosomes. combination classical molecular dynamics simulations and quantum chemical calculations, the subsequent development inactive derivative positive charge tertiary amine on trienyl arm induces G selectivity. Moreover, identified DDX3, another is alternative target with same effects eIF4A. Our results provide example sequence-selective anchoring proteins inhibition protein synthesis small-molecule compounds. Here authors report DMDA-PatA, anti-tumor compound, functions as translational inhibitor. drug clamps DDX3 motif, providing steric hindrance

Language: Английский

Citations

4
Iron-Catalyzed Regioselective C═C Bond Migration and Reductive Deuteration DOI

Qiuting Zhao,

Congrong Li,

Hongjie Gao

et al.

The Journal of Organic Chemistry, Journal Year: 2025, Volume and Issue: unknown

Published: April 28, 2025

We report a well-defined multifunctional iron catalyst, Cp*Fe(Ph2PN = C5H4N), that promotes the rearrangement of β,γ-unsaturated ketones, esters, and amides to their α,β-isomers, enabling regioselective C═C reductive deuteration. This iron-catalyzed protocol showcases synthesis diverse range α,β-dideuterated organic compounds, demonstrating broad substrate compatibility under mild conditions. Mechanism studies provide insights into bond relocation cooperative D2 activation.

Language: Английский

Citations

0