Polyhedron, Journal Year: 2023, Volume and Issue: 250, P. 116822 - 116822
Published: Dec. 30, 2023
Language: Английский
Nature Communications, Journal Year: 2025, Volume and Issue: 16(1)
Published: Feb. 6, 2025
Compared with rare-earth (RE)…heteroatom interaction, RE…π frequently used in facilitating regio- and stereoselectivity of olefin polymerizations, is seldomly to trigger catalytic C - H functionalization. Here, we describe a direct anti-Markovnikov hydroallylation reaction styrene derivatives 1-aryl-2-alkyl alkenes α-alkenes by use interaction. This protocol provides straightforward atom-efficient route for the synthesis valuable chain elongated internal (65 examples, up 99% yield, > 19:1 E/Z ratio). The proceeds via an allylic Csp3‒H activation pathway initiated site-selective deprotonation assistance cationic imidazolin-2-iminato scandium alkyl species followed alkene insertion into resulting scandium-allyl bond. A amount Lewis base additives, such as amine tetrahydrofuran (THF) show significant effects on reactivity selectivity. mechanism elucidated experimental studies theoretical calculations.
Language: Английский
Citations
4
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
Angewandte Chemie International Edition, Journal Year: 2024, Volume and Issue: 64(1)
Published: Sept. 17, 2024
Allylic sulfones are valuable motifs due to their medicinal and biological significance versatile chemical reactivities. While direct allylic C-H sulfonylation represents a straightforward desirable approach, these methods primarily restricted terminal alkenes, leaving the engagement of internal counterparts formidable challenge. Herein we report photocatalytic approach that accommodates both cyclic acyclic alkenes with diverse substitution patterns electronic properties. Importantly, obtained can be readily diversified into wide range products, thus enabling formal alkene transposition all-carbon quaternary center formation through sequential functionalization.
Language: Английский
Citations
5
JACS Au, Journal Year: 2024, Volume and Issue: 4(11), P. 4234 - 4248
Published: Sept. 18, 2024
With growing efforts pushing toward sustainable catalysis, using earth-abundant metals has become increasingly important. Here, we present the first examples of cobalt PC
Language: Английский
Citations
3
Journal of the American Chemical Society, Journal Year: 2025, Volume and Issue: unknown
Published: April 21, 2025
Transition-metal hydrides stand as indispensable intermediates in both energy conversion and organic synthesis. Their electrochemical generation represents a compelling sustainable approach, enabling precise control over the reactivity expanding scope of electrocatalytic hydrogenation isomerization. However, major challenge Ni-catalyzed is competing hydrogen evolution reaction (HER), which has led to various innovative strategies aimed at circumventing Ni-H formation. Here, we pursued an alternative approach by designing bifunctional ligand with pendant amine moiety promote This design enabled selective (semi)hydrogenation diverse range substrates, including terminal internal alkynes, alkenes, aldehydes, achieving unprecedented substrate scope. Remarkably, also demonstrated tunable positional selectivity for olefin isomerization employing different types proton sources. Our method exhibits excellent functional group tolerance, streamlining access pharmaceuticals their derivatives. Computational studies revealed crucial, noninnocent role source modulating metal hydride selectivity, either through bonding, direct protonation amine, or facilitation protodemetalation.
Language: Английский
Citations
0
The Journal of Organic Chemistry, Journal Year: 2025, Volume and Issue: unknown
Published: May 19, 2025
We herein report a dual visible-light photoredox- and copper-catalyzed Z-selective allyl trifluoromethylation reaction of allylamine by using trifluoromethylpyridinium salt (TFSP) as the trifluoromethyl radical precursor. Various thermodynamically disfavorable trifluoromethylated cis-enamides were accessible with moderate to good isolated yields. Cuprous oxide or copper nanoclusters crucial co-catalyst for this transformation.
Language: Английский
Citations
0
Organic Letters, Journal Year: 2024, Volume and Issue: 26(15), P. 3124 - 3129
Published: April 9, 2024
We report a single additive-responsive chromium-catalyzed system for selectively producing either of two different internal alkene isomers. The chromium catalyst, in the presence HBpin/LiOtBu, enables isomerization alkenes over multiple carbon atoms to give most thermodynamically stable same catalyst allows selective terminal one atom without an additive, exhibiting efficient and controllable transposition selectivity.
Language: Английский
Citations
2
ACS Catalysis, Journal Year: 2024, Volume and Issue: 14(17), P. 13174 - 13180
Published: Aug. 17, 2024
An additive-free manganese-catalyzed isomerization of terminal alkenes to internal is described. This reaction implementing an inexpensive nonprecious metal catalyst. The most efficient catalyst the borohydride complex cis-[Mn(dippe)(CO)2(κ2-BH4)]. operates at room temperature, with a loading 2.5 mol %. A variety effectively and selectively transformed into respective E-alkenes. Preliminary results show chain-walking elevated temperature. Mechanistic studies were carried out, including stoichiometric reactions in situ NMR analysis. These experiments are flanked by computational studies. Based on these, catalytic process initiated liberation "BH3" as THF adduct. double bond insertion M-H species, leading alkyl intermediate, followed β-hydride elimination opposite position afford product.
Language: Английский
Citations
2
Accounts of Chemical Research, Journal Year: 2023, Volume and Issue: 56(23), P. 3392 - 3403
Published: Nov. 13, 2023
ConspectusTransition metal complexes featuring an M═NR bond have received great attention as critical intermediates in the synthesis of nitrogen-containing compounds. In general, properties imido ligand these are dependent on nature center. Thus, tends to be nucleophilic early transition and electrophilic late complexes. Nonetheless, supporting can a dramatic effect its reactivity. For example, there sporadic examples complexes, often based strongly donating ligands. Building earlier works, this Article, we show that low-coordinate high-spin bis(carbene)borate Fe(II) complex is able access previously unknown reaction pathways, ultimately leading new catalytic transformations. We first focus synthesis, characterization, stoichiometric reactivity highly complex. The entry point for system intermediate-spin three-coordinate Fe(III) complex, which generated from Fe(I) synthon with organic azide. Alkali reduction leads series M+ (M = Li, Na, K) coordinated charge-separated K(18-C-6)) all been isolated fully characterized. Combined electronic structure calculations, results reveal alkali ions moderately polarize Fe═N according K+ ≈ Na+ < Li+. As result, basicity increases charged separated K+, Na+, Li+ validated by intermolecular proton transfer equilibria. impact counterion demonstrated through protonation, alkylation, hydrogen atom abstraction reactions. also directs outcome [2 + 2] reactions benzophenone, where coordination facilitates double metathesis. here, describe how unusual nucleophilicity revealed extended cycloaddition serves basis guanylation carbodiimides under mild conditions. More interestingly, exhibits ene-like alkynes, nitriles, alkenes. These transformations form alkyne nitrile α-deuteration pKa-dictated alkene transposition reactions, respectively. Mechanistic studies role metal-ligand cooperativity facilitating suggest avenues catalysis extend beyond classical nitrene chemistry.
Language: Английский
Citations
5
ChemCatChem, Journal Year: 2024, Volume and Issue: unknown
Published: June 6, 2024
Abstract Transition metal catalysis plays a pivotal role in chemical synthesis. Noble metals often grab significant attention organometallic due to their high reactivity. However, the serious issues associated with these such as low abundance, toxicity, geopolitical limitations, and volatile prices are driving scientific community discover sustainable alternatives. In this context, iron appears be first choice an alternative its unique properties, including range of stable oxidation states, Lewis acidity, abundance earth‘s crust, toxicity. Over past two decades, substantial progress has been made catalysis. This overview examines recent developments iron‐catalyzed industrially relevant transformations hydroformylation, olefin isomerization, hydrosilylation, hydrophosphination, carbonylation, Wacker‐type oxidation, plastic depolymerization. As witnessed throughout review, performance can significantly altered by suitable ligand selection tailoring electronic steric properties center. While noble remain industry work‐horse, is inching closer extensive understanding, it may replace near future.
Language: Английский
Citations
0